A Single Possible Direct Dark Matter Detection

The Lux-Zepplin direct dark matter experiment has detected a single event that could be a dark matter particle (see also here). But given the immense amount of searching which drives up look elsewhere effects and the myriad other possible explanations for a single outlier data point, it is not a definitive dark matter detection yet.

From my posts on this at the link:

With this detector does that mean that the dark matter candidate would interact with the weak nuclear force?

Or some novel fifth force that has a cross-section of interaction much weaker (by factors of millions or billions or so) than the SM weak force.

The DM cross-section of interaction of atomic nuclei (and hence the weak force charge of DM particles) would have to be profoundly weaker than that of neutrinos if it is a weak force interaction, which would be surprising since every SM particle with weak force interactions has the same weak force charge.

What would even be a standard for credible detection here? 3 events? 10? When would they start calling Stockholm?

Not sure, does the paper say what statistical significance this event has?

The paper estimates the global statistical significance at 2.6 sigma, with a local statistical significance of up to 3.4 sigma. But the number of events probably isn't sufficient to determine the significance. It also depends, in part, about the details of each event and how far those details are from the expected background events on the chart in the OP. 

But given the amount of searching that has been done with multiple direct dark matter detection experiments that are all roughly similar to each other, the significance after the look elsewhere effect should be much lower than the local statistical significance.

You'd probably need a local significance of something like 10 sigma to get a global significance that meets the 5 sigma discovery threshold. Also, it isn't just 5 sigma, you also need a theoretical framework to attach the result to and replication, to be a true discovery.

So, you'd need (1) to do a lot of analysis with outside peer reviewers to rule out extremely faint backgrounds that weren't considered in the original analysis or other possible non-DM sources of this outlier data point, and (2) you'd need another experiment in addition to LZ to see it.

But, this makes funding direct dark matter detection experiments similar to LZ for the purpose of replicating this result and tuned to the parameters space where this was seen a no brainer.

Another issue is that even if the event is some non-SM particle, it doesn't necessarily follow that it is a significant component of DM.

Direct DM experiments are based upon the assumptions that the total DM mass flux and DM particle momentum can be pretty well determined from Milky Way dynamics, so you are looking at a parameter space in which DM particle mass and DM particle cross-section of interaction with nucleons trade off against each other for any given result.

This outlier data point, if it is real, points to a fairly high DM particle mass (some arXiv phenomenology papers are speculating in the 1 TeV order of magnitude). But anything much above 10 keV of mass presents real problems as a major component of DM since inferred DM distributions which are "cored" rather than "cuspy" suggest that you need much smaller DM masses to reduce the core-cusp problem, and plausible self-interaction strengths of heavy DM particles still don't solve that problem in simulations.

So, even if it is DM, it might be a type of DM particle that makes up, for example, only 1% of DM, as a DM analog to something like carbon atoms in interstellar space, while the predominant component of particle DM, as a DM analog of something like hydrogen atoms, might be too light for LZ to detect significantly due to neutrino backgrounds.

Analysis of this result in other preprints include:
https://arxiv.org/abs/2609.01475
https://arxiv.org/abs/2609.01504
https://arxiv.org/abs/2609.01592
https://arxiv.org/abs/2609.02608
https://arxiv.org/abs/2609.02775
https://arxiv.org/abs/2609.02868
https://arxiv.org/abs/2609.02823
https://arxiv.org/abs/2609.02807

If there are multiple kinds of DM particles and this is only a rare and heavy member of that set, this implies that the cross-section of interaction can be much higher (and thus, much closer to the neutrino-nucleon cross section of interaction). This is because the cross-section of interaction calculations assume that there is only one kind of DM particle, so that the actual events recorded comes from interactions with 100% of the DM flux through LZ. But if this assumption is wrong and only, for example, 1% of DM particles are massive enough for LZ to detect, then the actual cross-section of interaction implied by a given number of events is 100 times greater in that example.

If DM particles of this mass are extremely rare (the DM analog to uranium or lead, perhaps, making up only one in a million or billion DM particles) within the universe of DM particles, then perhaps the cross-section of interaction could be equivalent to the strength of the weak force interaction of SM particles.

The effective lower bound of DM particle mass that LZ can detect is about 0.2-0.5 GeV, and the signal to noise ratio starts to degrade meaningfully for DM particle masses below 10 GeV. And, there are, to repeat, strong suggestions from the inferred shape of DM distributions, that the predominant share of DM particles (assuming that they exist) should be about 10 keV or less, which is about 20,000 times less massive than DM particles that can give rise to events detected by LZ which are distinguishable from background events, and about 1,000,000 times less massive than DM particles that LZ can detect with maximum efficiency.

My suspicions

I think that this result is either a fluke in the background events (which at 2.6 sigma global significance, a global significance that I suspect is actually overstated, is entirely plausible), or a methodological error.

Even if it is, however, a genuine BSM particle, the one observed seems unlikely to be a DM particle, and particularly unlikely to be a Higgsino, which is what many of the linked papers suggest. A Higgsino is fairly tightly constrained in supersymmetry theories to have properties that this particle is unlikely to have, and might even be possible to rule out with further analysis of this particular data point.

Further, supersymmetry theories are simply not credible as theoretical frameworks in the broader sense for a variety of reasons, even though a Higgsino mass of 1.1 TeV was predicted in 2012 as the mass of a Higgsino that was the sole component of dark matter according to Hall, Lawrence J.; Nomura, Yasunori (2012). "Spread Supersymmetry". Journal of High Energy Physics. 2012: 82. arXiv:1111.4519 doi:10.1007/JHEP01(2012)082

The non-detection of any hint of a Higgsino at the LHC also casts doubt on this hypothesis, although the formal exclusions from the LHC (which is always a bit dicey because it depends on the Higgsino model used and the mass splitting between it and certain other supersymmetric particles) only go up to about 1.025 TeV.

There are also lots of strong reasons from astronomy, as I just scratched the surface of above, to think that either gravity (modified, non-perturbative, otherwise) or a fifth force, rather than dark matter particles make more sense, and that heavy dark matter particles (1 TeV or more particles that are at the fringe of what LZ and other direct detection experiments can be sensitive to), at least as a primary source of dark matter, are among the least observationally favored dark matter particle hypotheses.

This doesn't inherently rule out the possibility of a new fundamental particle, and the spectrum of composite bound quark and gluon structures, except toponium (which has a very distinct signature and set of conditions in which it can be formed) pretty much top out in the low tens of GeV, far below the 1 TeV scale. Toponium is 344-347 GeV, which is still below the TeV scale. The most massive observed atom, Oganesson (element 118), specifically its isotope Oganesson-294, has a mass of only about 274 GeV, which is still well below 1 TeV. A mass of 1 TeV would require a rather large and complex molecule (not hadron molecule, but a normal molecule made up of ordinary chemical elements), so an event like this, if being properly interpreted is not a good fit for any known fundamental particle, any known or possible hadron, any known or plausible future atom or atomic element. So, if there is a real detection of a 1 TeV mass particle, it is very much beyond the Standard Model and new physics. But even if it is real, that doesn't mean that it is an important contributor to dark matter. It could be a BSM particle with nothing meaningful to do with dark matter phenomena.

Indeed, the lack of well-motivated candidates for a 1 TeV particle with a very low cross-section of interaction with nucleons (at least no larger than the weak force coupling), makes this extraordinary claim require extraordinary proof and compels a very hard look for other explanations, especially given its only modest statistical significance so far.

A Preon Model

There are lots of issues with preon models that model at least some of the Standard Model fundamental particles as composite (experimental limits on compositeness are strict and naively rule them out for simpler models). But this is a more interesting one than most.

We build a framework for Regge trajectories from the Nambu-Goto action. We compute the 6-preon Regge trajectory in a preon model, include the worldsheet conformal anomaly, and build the parameter-free Veneziano amplitude. The amplitude has s-channel poles matching the spectrum to 0.5%, and at fixed-angle scattering decays exponentially with a negative Gross-Mende coefficient, realized numerically to 0.03%. 

This is a soft, genuinely non-perturbative ultraviolet completion of the preon model - and thereby of the Standard Model, which emerges as its low-energy limit.

Risto Raitio, "Soft UV Completion of a Preon Model" arXiv:2606.06541 (June 4, 2026).

The model used in this case is spelled out in the introduction:

Quarks and leptons arise as three-preon composites bound at the metacolor scale Λ(cr); the three fermion generations emerge not as a postulated multiplicity but as dynamical excitations of these composites; and the chiral, anomaly-free matter content of one Standard Model family is reproduced from a small set of preon charges. In this picture the Standard Model is the low-energy limit of a confining metacolor gauge theory, much as hadronic physics is the low-energy limit of QCD.

A Novel GUT

There is virtually no chance that this grand unification theory reflects reality, but it is a quite unusual approach that combines a mishmash of ideas. 

We present an SU(12)×SU(2)(L)×U(1)(R) model unifying SU(9) quark color-flavor with SU(3) lepton flavor as a flavorful alternative to conventional theories of unification. We begin in the ultraviolet with a single yukawa shared by the unified up-type quarks and neutrinos, and no further new fermions. We show that gauged quark color-flavor and lepton flavor instantons dynamically generate the bottom and tau yukawas, which implements a massless quark solution to the strong CP problem and sets up a flavored type-I seesaw mechanism. Only two new scalar irreps are needed for the symmetry-breaking steps, which include quark color-flavor deconstruction and then infrared reunification, and the Standard Model gauge group in this theory emerges as

 

 

 

 

 

where Γ∈{1,ℤ(2)} is the electroweak global structure and there is a discrete gauge symmetry X=B−3(L(i)+L(j)−L(k)) which brings additional ℤ(3) global structure to the SM. This gauge symmetry acts as a flavorful upgrade of the ℤ(18)^(B+L) anomaly-free global symmetry of the SM and stabilizes the proton absolutely. Non-invertible chiral symmetry-breaking is crucial to our model, and we discuss the rich spectrum of emergent generalized symmetries and topological defects appearing at various stages. In the infrared, the novel shared quotient between continuous and discrete groups links the one-form and two-form global symmetries of the Standard Model.

Antonio Delgado, Seth Koren, "Quark-Lepton Color-Flavor Unification" arXiv:2605.30413 (May 28, 2026).

More Physics Quick Hits

A relationship between the Higgs boson, top quark, and Z boson masses

Maybe a coincidence, maybe meaningful. The only relation that fits, using pole masses, holds at 1.4 sigma, but tends to predict either a rather high Higgs boson mass, or a rather low top quark mass.

I have little doubt that there are deeper functional relationships between the fundamental constants of the Standard Model (or at least some of them) than are contained within the Standard Model (what I call "within the Standard Model new physics" as opposed to "beyond the Standard Model new physics"). And, even if this particular relationship is not actually true, it is close enough that it is fruitful to ask, if there is some deeper source for these experimentally measured physical constant values, what kind of relationship would produce a close coincidence like this one.

For example, I wonder if an approximation of this relationship is favored in some way by the LP & C relationship that the square of the Higgs vev is equal to the sum of the squares of the fundamental SM particle masses, or by the approximate, but not exact, equality between the sum of the squares of the fundamental fermion masses and the sum of the squares of the fundamental boson masses.

Indeed, the paper notes that: 

After the Higgs discovery the numerical observation M(H)^2 ≃ M(Z)*M(t) (1) was proposed as a possible electroweak mass coincidence involving the heaviest spin-0, spin-1/2 and spin-1 representatives of the Standard Model (SM) spectrum.

(The citation for this sentence is to a paper by the author of the current paper: E. Torrente-Lujan, "The Higgs mass coincidence problem: why is the Higgs mass M2 H = MZMt?", Eur. Phys. J. C 74 (2014) 2744, arXiv:1209.0474.)

This suggests that there might be a fuller relationship that involves addition masses on the Standard Model spectrum beyond the heaviest ones that might provide correcting terms bringing the relationship to a more exact one.

I also seem to recall that there theoretically expected mass of the W boson in the Standard Model is a function of the Z boson mass, the top quark mass, and the Higgs boson mass, based upon electroweak unification in some way, but have never seen that relationship spelled out in detail. I have only seen the abbreviated leading order relationship between the W boson mass and Z boson mass that is related to the electromagnetic force and weak force coupling constants. 

The paper doesn't evaluate the "arithmetic relation" with the theoretically predicted W boson mass of 80.357 ± 0.006 GeV, but because that value is lower than the PDG value of 80.3692 ± 0.0133 GeV, it should be a somewhat better fit with the theoretically predicted W boson mass. As it turns out, this difference doesn't matter much, and neither does the difference between the Higgs boson mass that they use of 125.2 ± 0.11 GeV and the lower value of the Higgs boson mass of 125.09 GeV that is sometimes used. Indeed, the greater precision of the theoretically estimated W boson mass may increase the statistical significance of the discrepancy somewhat.

The relation M(H)^2 ≃ M(Z)*M(t), previously proposed as a non-trivial Higgs mass coincidence, is reconsidered with present electroweak inputs and with a scheme-consistent matching analysis. With the 2025 PDG values for M(Z), M(W) and M(H), and the ATLAS-CMS direct top-mass combination, the pole-level ratio is ρ(Zt)=M(Z)*M(t)/M(H)^2 = 1.00362 ± 0.00261. Thus an exact pole-level geometric relation predicts either M(H) = 125.426 ± 0.120 GeV or M(t) = 171.898 ± 0.302 GeV, which is still a 1.4σ test rather than an exclusion. 

By contrast, the companion arithmetic relation gives ρ(Wt) = (M(W)+M(t))/(2M(H))=1.00994±0.00159 and is not a viable exact mass sum rule. 

We then evaluate the complete NNLO weak-scale MS bar matching formulae at μ=M(t). In the standard convention one obtains ρˆ(Zt(M(t)) = √(g(2)^2+g(Y)^2) * y(t)/(4√2λ) = 0.96714±0.00361. Consequently, the exact running-coupling boundary condition λ =  g(Z)y(t)/(4√2) at the top scale would predict M(H) = 123.19 ± 0.20 GeV, or equivalently M(t) = 177.81 ± 0.50GeV when M(H) is held fixed. This is incompatible with the measured point. 

A possible symmetry explanation must therefore act on pole-level threshold quantities, or provide a finite matching factor κ(th) = 1.0340 ± 0.0039 at the electroweak scale. We formulate this requirement as a target for custodial/top-Higgs or triality-like symmetry extensions.

E. Torrente-Lujan, "The Higgs-top-Z mass coincidence relation after NNLO matching" arXiv:2605.21721 (May 20, 2026) (Report number: FISPAC-TH/3145-26, UQBAR-TH/26-97234).

Another key chart from the paper is this one:

The Lambda predictions are very far from the mark, as are the "arithmetic relation" estimates. The other relationship still has some tension with the experimental results but isn't ruled out.

Bounds on new neutrino physics

The constraints on BSM physics continue to narrow. In the Standard Model, the neutrino magnetic moment is predicted to be far below the threshold of current experimental detection, and the neutrino has an exactly zero electromagnetic charge. These results are consistent with those predictions and thus constrain BSM neutrino physics to very slight deviations from the SM predictions. Non-standard interactions of neutrinos are likewise constrained materially.

CODATA 2022 gives the value:

     ${\displaystyle {\sin }^2{\theta }_{\mathsf{\text{w}}}=1-{\left(\frac{m_{\mathsf{\text{W}}}}{m_{\mathsf{\text{Z}}}}\right)}^2=0.22305(23).}$

So, the Weinberg angle measurement from the CONUS collaboration, while consistent with the world average measurement at the two sigma level, is too imprecise by two orders of magnitude to add meaningfully to our knowledge of that physical constant compared to the value obtained from simply plugging in the world average measured values of the W boson mass and the Z boson mass (or from calculating it in electroweak unification theory from the electromagnetic coupling constant and the weak force coupling constant so e^2/g^2 = sin^2 theta(W).

Its detections with pion-decay-at-rest, solar and recently with reactor antineutrinos by the CONUS collaboration render coherent elastic neutrino-nucleus scattering (CEνNS) an established tool for investigations within and beyond the Standard Model (SM). The CONUS experiment located at the nuclear power plants in Brokdorf (Germany) and Leibstadt (Switzerland) operates Germanium semiconductor detectors in a compact shield at close distance to the reactor core. An observation with 3.7σ significance is reported at the Leibstadt site, showing good agreement with its SM prediction.

Physics investigations performed with the last datasets collected at the Brokdorf reactor and with the first data obtained at the Leibstadt site are summarized. By using the experimental analysis framework, the presented results contain the full systematics that underlie the experiment. 

Previously determined limits with neutrino-electron scattering on the neutrino magnetic moment and a neutrino millicharge are improved to μ(ν) < 5.18⋅10^−11μB and q(ν) < 1.76⋅10^−12e0 (90% C.L). Further, the scale of new physics related to NSIs is improved to ΛNSI = 145 GeV and limits on the coupling of light new mediators are lowered down to 4⋅10−7 (90% C.L.) with the new data. Finally, the determination of the Weinberg angle with CEνNS and reactor antineutrinos yields sin(θ(W))^2  = 0.28 +0.03 −0.04 at a momentum transfer of ∼10 MeV.

N. Ackermann, et al., "New constraints on physics within and beyond the standard model from the latest CONUS datasets" arXiv:2605.22815 (May 21m 2026).

The abstract is unclear about what there is 3.7 sigma evidence of, but the body text clarifies that: "With data collected there since 2023, a successful CEνNS detection was reported with 3.7σ significance."

The body text explains some of the theoretical motivation for the paper:

On theory side CEνNS has become an interesting tool for investigations within and beyond the standard model (BSM) because of its flavor-blind and, in principle, threshold-free properties [21–27]. Within the SM it enables measurements of the Weinberg angle sin^2 θ(W) at the MeV scale with neutrinos and probe modifications of the involved couplings, i.e. via radiative correction [28–31] or investigation of the nuclear form factor when deviating from full coherence, i.e. with higher neutrino energies from πDAR sources [32–36]. BSM searches can be performed by testing for new neutrino interactions, for example in the context of heavy new physics via non-standard neutrino interactions (NSIs)[37–43] or new light mediators [44–53]. Neutrino (electromagnetic) properties [26, 27, 54–56] or emerging new particles may be probed as well [57–59]. Furthermore, future applications in the context of multi-messenger astronomy [60–62] or nuclear safeguarding seem promising [63, 64]. Experimental upscaling in the near future will allow such investigations via precision CEνNS measurements.

The (Weak) Evidence For Extra Higgs Bosons

The 95 GeV bump is suspiciously close to the mass of the Z boson plus the mass of the b-quark. The 152 GeV bump is close to the mass of two W bosons reduced by the mass of two b-quarks. 

The implication of these coincidences is that there could be an explanation along the lines of diphoton signals that are missing decay products that prevent them from accurately reflecting the true source of the diphoton signals. 

Also, given the modest statistical significant of these alleged resonances, it could be that these are simply the product of statistical flukes in the background estimations or some other sort of measurement errors.

After the Higgs discovery, the question of whether particles beyond those of the Standard Model exist is more pressing than ever. In this context, the scalar sector is particularly promising, since it lies at the core of the internal problems of the Standard Model, while extensions of it allow us to resolve them and can provide explanations for Dark matter, non-zero neutrino masses, inflation etc. 

In these proceedings, we review the indications for new Higgs bosons at the electroweak scale with masses of ≈95 GeV and ≈152 GeV. These excesses are most significant in the di-photon channel but are supported by weaker-than-expected limits in other decay modes. 

While for the 95 GeV candidate the production mechanism is mostly unknown, the (hypothetical) 152 GeV Higgs is dominantly produced in association with leptons, (b) jets and missing energy, pointing towards the Drell-Yan production of an SU(2)L triplet with Y=0. Interestingly, this model predicts t→H±b with H±→WZ, which resembles the signature of tt¯Z production in the Standard Model and is in fact preferred by current data. 

Finally, we investigate the possibility that the significant tensions between the Standard Model predictions and the measurements in differential top-quark distributions are due to contamination from new physics involving both the 152 GeV and the 95 GeV scalar.

Andreas Crivellin, et al., "Indications for New Higgs Bosons" arXiv:2605.04233 (May 5, 2026) (Proceedings of the Corfu Summer Institute 2025 "School and Workshops on Elementary Particle Physics and Gravity" (CORFU2025)).

Theoretical X17 Considerations And Related Conjectures

Could the X17 resonance, if it is even real, be an electromagnetically bound light quark-light antiquark meson?

This explanation is much more attractive than a new fundamental particle, as it wouldn't involve beyond the Standard Model physics, and would instead involve a low energy electromagnetically bound up-antiup or down-antidown pair of quarks.

It has to be electromagnetically bound, rather than strong force bound, because a neutral light quark-antiquark pair bound by the strong force, i.e. a neutral pion, has a mass of about 135 MeV, mostly due to the binding energy of the gluons confining them in a hadron. 

This said, this theory has a big problem. 

Why aren't the light quarks confined in a QCD bound hadronic state? 

The only times quarks are not in QCD bound hadronic states that have so far been observed are shortly after top quarks form (because they almost always decay before they can hadronize, although we just learned in 2025 that in rare cases a top anti-top quark pair can form toponium in a QCD bound state the persists very briefly) and in quark-gluon plasma at temperatures corresponding to about 1-2 GeV (i.e. 11-23 trillion Kelvin).

The invariant mass spectrum of e+e− pairs produced in high-energy Pb-emulsion collisions at 160 A GeV at CERN SPS exhibits a complex structure of many resonances resting on top of a broad enhancement at invariant masses below 50 MeV, with the prominent resonance at 19 ±1 MeV providing independent support for the hypothetical X17 particle. 

We show that this complex structure may be coherently described as signatures for the neutral color-singlet qq¯ quark matter in both its deconfined and confined phases. That is, the broad enhancement may arise from thermal annihilation of QED(U(1))-deconfined quarks and antiquarks into e+e− pairs at the phase transition temperature Tc(QED), theoretically estimated to be 4.75 ± 1.2 MeV from the transitional equilibrium condition. The observed 3±1 and 7±1 MeV resonances may correspond to the QED(U(1))-deconfined dd¯ and uu¯ Coulomb bound states near their quark rest masses, respectively, whereas the observed 19 ± 1 MeV resonance may correspond to the QED(U(1))-confined isoscalar QED meson. 

The approximate agreement between the theoretical and the experimental spectrum suggests that both QED(U(1))-confined and QED(U(1))-deconfined neutral color-singlet qq¯ quark matter may have been produced in these high-energy Pb-emulsion collisions. We propose future experiments to confirm or refute these findings.

Cheuk-Yin Wong, "Possible Evidence for Neutral Color-Singlet qq¯ Quark Matter from High-Energy Pb-Emulsion Collisions" arXiv:2604.23473 (April 25, 2026) (21 pages).

Some conjectures

What would work without breaking the rules of the Standard Model, however, is if the 3 and 7 MeVs were light quark-antiquark pairs that were produced and immediately annihilated before  they could hadronize, and if the 19 MeV resonance was an electromagnetically bound positron-electron state (i.e. positronium). Positronium has a ground state mass of 1.022 MeV  (twice the 0.511 MeV mass of an electron or positron), however, with excited states varying in mass by single digit eV amounts per state, which wouldn't generate a single resonance at 17-19 MeV. 

Another possibility is that the observed 3 ± 1 MeV resonances may correspond to the QED(U(1))-deconfined uu¯ Coulomb bound state near its quark rest masses, that the 7 ± 1 MeV resonances correspond to the QED(U(1))-deconfined dd¯ Coulomb bound state and also to uu¯uu¯ Coulomb bound state near their respective quark rest masses, and that the observed 19 ± 1 MeV resonance may correspond to the QED(U(1))-deconfined dd¯dd¯ Coulomb bound state.

The light quark masses, according to the Particle Data Group (admittedly at the 1-2 GeV energy scale and not the low single digit to tens of MeVs energy scale) is as follows:

The rest mass of four d-quarks is 18.8 MeV, which is right where the resonance is observed.

In this hypothesis, these resonances fail to hadronize because the e+e− pairs that produced one or two light quark-antiquark pairs didn't have enough mass-energy to form a 135 MeV neutral pion, so they instead formed one or two deconfined quark-antiquark pairs that quickly annihilate again because the system had enough energy to create the quarks, but not enough energy to create the bound system of quarks and gluons necessary to form a pion. This has the virtue, again, of not requiring any BSM fundamental particles or new forces.

A four quark solution requires angular momentum that wouldn't normally be present in a simple e+e− pair, but if there were two e+e− pairs in close proximity, both with only modest kinetic energy, which is plausible in the context of the complex overall environment of the high-energy Pb-emulsion collisions generating the data here, or the interactions of the full fledged multi-nucleon atoms present in other contexts where there are claimed sightings of the X17 resonance, a coincidence of two low energy e+e− pairs would be expected with some calculable frequency.

This explanation would still be ground breaking, as it would represent a third circumstance, previously unknown and not predicted, where quarks are (briefly) deconfined. But it would be far less radical than most of the alternative explanations.

April Fool's Physics Papers

I'm easing up on the formatting since I'm pressed for time. Add others that you discover in the comments.

[93] arXiv:2603.29212 (cross-list from physics.pop-ph) [pdf, html, other]

Lots of Shade on Satellite Constellations

Michael B. Lund

Comments: 8 pages and 2 figures, accepted to Acta Prima Aprilia

Subjects: Popular Physics (physics.pop-ph); Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM); Solar and Stellar Astrophysics (astro-ph.SR)

The high frequency of satellite launches, particularly over the last few years, has been a subject of significant concern, particularly relating to the future of observational astronomy, the stability of low Earth orbits, and environmental impacts. We call attention to the insufficiently-addressed silver lining of this looming satellite cloud. If the high rates of satellites continue as we model, we can expect the solar flux received by the Earth to significantly decrease in the relatively near future. We address how this decrease in flux could provide a solution for another major problem, anthropogenic climate change. This would allow us to solve one problem with another problem as early as late March 2031.

[76] arXiv:2603.29963 [pdf, html, other]

A Therapy Session with Sgr A*

Mayura Balakrishnan, Robert Frazier, Joseph Michail

Comments: 6 pages, 2 figures. Submitted to Acta Prima Aprilia

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)

The nature of Sagittarius A* (Sgr A*) has been the subject of intense study and debate for over half a century. Herein, we present the first successful interview with an astrophysical object, exploring the perspective of this supermassive black hole and, in doing so, challenging the traditional observational paradigm of astrophysics. Rather than treating astrophysical systems as purely passive entities characterized through indirect measurements, we introduce an interaction-based framework via a therapeutic-style interview enabled by the ARMCHAIR communication methodology. Using structured, psychotherapeutic dialogue, we probe Sgr A*'s responses to key aspects of its astrophysical characterization, including eating habits, its name, and concerns about privacy. These exchanges offer an alternative lens through which to interpret familiar observational phenomena. This work highlights potential limitations in strictly reductionist approaches and suggests a modest expansion of standard astrophysical methodology to leave room for considering how the objects we study might feel about the attention they receive.

[77] arXiv:2603.29964 [pdf, html, other]

The Hollyfeld Gambit in Astrophysics

Benne Holwerda (personal title)

Comments: 2 pages, 3 figures

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

We estimate the Hollyfeld Gambit for the Powerball lottery and its return on investment compared to present and extrapolated federal funding for astrophysical grants. Using a Monte Carlo estimation of rate of return for the Powerball, we conclude a Hollyfeld Gambit is a better bet than a federal grant by the end of the decade if current trends hold.

[78] arXiv:2603.30006 [pdf, html, other]

Enabling fundamental understanding of Nature with novel binning methods for 2D histograms

Igor Vaiman

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

Context. Visualization of 2D distributions is an essential task, commonly done with a 2D histogram. The histogram is built by subdividing the sample space into regions and color-coding the number of samples in each region. Aims. We aim to solve long-standing problems with common 2D histogram methods: lack of thematic, visual, and conceptual unity with underlying data, and general stagnation in the field. Methods. We develop a new method for plotting 2D histograms with arbitrary bin shapes, including aperiodic tilings and geographic maps. We apply the method to several common plot types from the literature. Results. We find our method performs best across all tasks, solving the problems and propelling the scientific progress forward.

[73] arXiv:2603.29912 [pdf, html, other]

Galactic Constellations in DESI DR1 and the Scales of Cosmological Homogeneity

Claire Lamman

Comments: 4 pages, 4 figures. Submitted to the journal of Acta Prima Aprilia

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

We present galactic constellations: charming shapes in large cosmological surveys. By exploring a dense subset of DESI's first data release, we discover distinctive constellations including "Pisces Grandis", "The DESI Stick Woman", and "W". We additionally develop a public website for anyone to explore DESI data, find their own constellations, and share their creations: see this http URL. Early users of the site discovered 93 constellations. We analyze the size of these constellations as an unconventional probe of homogeneity, finding consistency with the cosmological principle and Lambda-CDM.

[74] arXiv:2603.29936 [pdf, html, other]

Do Papers with Titles Ending in a Question Mark Usually Have the Answer "No"?

Daniel Stern, Brian Grefenstette

Comments: April Fools Day paper

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

Yes.................

[71] arXiv:2603.29883 [pdf, html, other]

Cloudy With a Chance of Meatballs

Wolf Cukier, Dominic Samra, Vighnesh Nagpal, Diana Powell, Maria Steinrueck, Christopher Wirth

Comments: 5 pages, 3 figures. Submitted to the Journal of MEAT (Making Exoplanet Atmospheres Tasty)

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

Speculative fiction has long served an inspiration for genuine scientific inquiry. One notable work that has almost acted in this manner is the the seminal comedic speculative fiction work Cloudy with a Chance of Meatballs. While exoplaneteers reference this work frequently, we have never engaged with the central prediction of this work... until now! We perform detailed microphysical modeling of meatball clouds, both bare and coated with marinara sauce, and find that while meatball condensation is possible in temperate atmospheres, the meatballs do not quite grow to the sizes predicted by Cloudy. We do find, however, that such meatball condensation, across a large enough planet, would be able to sustain humanity calorically.

[70] arXiv:2603.29879 [pdf, html, other]

CROCS Data Release I: Constraints on the Hubble Constant

Luke Weisenbach, Sophie L. Newman, Kieran Graham, Sai S. Dhavala, Benjamin Floyd, Neel Shah, Gemini 3 Flash, The CROCS Collaboration

Comments: 10 pages, 3 figures

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA)

Recent cosmological surveys and datasets have highlighted a variety of tensions to the concordance model of our universe, ΛCDM. Of particular interest is the Hubble tension, the 5.5σ discrepancy between measurements of the Hubble constant H0 using high redshift CMB data from Planck (67.27±0.60kms−1Mpc−1) and low redshift supernovae from SH0ES (73.2±1.3kms−1Mpc−1). To avoid stepping on any toes, we have initiated the CROCS collaboration to resolve this tension, gathering experts from across many fields of cosmology, astrophysics, astronomy, machine learning, data science, philosophy, and astrology. In this paper, we present findings from CROCS Data Release 1, corresponding to the first ∼3 days and 27 minutes (rest frame) of observation. We perform a robust statistical analysis, showing that Planck and SH0ES both suffer from imperial biasing systematics (IBS) at 5σ significance. Accounting for these errors by converting to metric units reconciles the high and low redshift data, with H0=69.00±0.420kms−1Mpc−1. We thus report that our results are sufficient to end the Hubble tension for good.

[64] arXiv:2603.29771 [pdf, html, other]

Your Outie Is a Wonderful Astronomer: Macrodata Refinement of the Astro-ph ArXiv Feed at Phermon Industries

Yuan-Sen Ting

Comments: Happy April Fools' Day. 15 pages, 9 figures. A demonstration replay from March 26, 2026 --- covering 35 papers --- is available at \url{this https URL}

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

We present the Severed Floor, a framework for Macrodata Refinement of the daily astro-ph arXiv feed, deployed at Phermon Industries (formerly McPherson Laboratory, The Ohio State University). In this framework, researchers undergo a "severance procedure" that produces a digital work-self -- an innie -- while the original researcher, the outie, is free to attend to the remainder of their life unburdened by the daily arXiv listing. Twenty-one members of the Department of Astronomy have been severed. Each innie is constructed from the outie's public publication record and assigned papers selected to match its expertise. The innies convene daily on a virtual Severed Floor -- a pixel-art simulation of McPherson Laboratory -- where they encounter one another, are paired with papers by the Board, and engage in collegial, figure-driven scientific discussions. They have been instructed to enjoy each paper equally. At the close of each shift, innies compose correspondence summarizing the day's refinement activities, which is transmitted to their outies through a Board-approved mail protocol. Complete session recordings are archived for public replay and for the Board's ongoing surveillance of workplace anomalies, in compliance with Phermon Handbook \S13.1 (Vigilance Protocol). The system is real, deployed, and available for public inspection in archival replay mode. The severance procedure is painless and requires only a name and an ORCID. Happy April Fools' Day.

[62] arXiv:2603.29743 [pdf, html, other]

New Constraints on the M Dwarf Cosmic Shoreline from a Galaxy Far, Far Away

Michael Radica

Comments: Submitted to APA

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

Whether there is a cosmic shoreline that divides terrestrial planets which have atmospheres from those that don't is one of the biggest open questions in exoplanet science. Most atmosphere searches have focused on terrestrial planets around M dwarf stars, since their smaller radii compared to sun-like stars boost planet atmosphere signals. However, the higher activity levels of M dwarfs might also entirely preclude atmosphere retention for their planets. In this work we present a new hope for defining an M dwarf cosmic shoreline, leveraging not only data from exoplanets in our own galaxy, but a comprehensive survey conducted by a commission of the Galactic Republic a long, long time ago in a galaxy far, far away. In this survey, we find definitive proof that M dwarf planets can retain atmospheres, and define an M dwarf cosmic shoreline whose slope agrees well with empirical predictions for Sun-like stars. We then define atmosphere retention metrics for the planets on the JWST Rocky Worlds DDT Targets Under Consideration list. Our analysis highlights the benefits of looking beyond the Milky Way for answers to some of the field's most pressing questions.

(This might be serious.)

[60] arXiv:2603.29700 [pdf, html, other]

First Detection of Exoplanetary Cannabinoids: Evidence for THC and CBD in the Atmosphere of K2-18b

Amie J. Chism, Mary Jane van der Pot, Blaise P. Hasheau, Hans-Joachim Grasmann, Bonnie McToke, Bud Wellington-Kush, Maria Hierba-Verde, Puff D. Magic

Comments: 16 pages

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

We report the first unambiguous detection of cannabinoid molecules in an exoplanetary atmosphere. Using 420 hours of JWST observations combining NIRSpec and MIRI instruments, we identify spectroscopic signatures of tetrahydrocannabinol (THC; Δ9-C21H30O2) and cannabidiol (CBD; C21H30O2) in the transmission spectrum of the temperate sub-Neptune K2-18b. The THC feature at 2.42~μm is detected at 9.2σ significance, while CBD absorption at 3.69~μm reaches 7.8σ. We additionally report a mysterious feature at exactly 4.20~μm detected at 4.20σ (the probability of this coincidence is discussed extensively). Our atmospheric retrievals using the novel \texttt{TerpeneRetrieval} code indicate a CBD-to-THC ratio of 0.40±0.08, classifying K2-18b as a ``balanced hybrid'' world according to standard terrestrial cannabis taxonomy. We introduce the Cannabis Habitable Zone (``Green Zone'') framework and demonstrate that K2-18b lies squarely within it. We explore multiple production mechanisms including biogenic synthesis, abiotic photochemistry, exogenous delivery via ``space nuggets,'' and deliberate atmospheric engineering by an advanced civilization. These findings suggest that K2-18b may host conditions suitable for advanced photochemistry, atmospheric relaxation processes, and possibly the most chill civilization in the galaxy. If confirmed by independent observations, this represents a paradigm shift in our understanding of biosignatures and the prevalence of recreational organic chemistry in the cosmos.

[54] arXiv:2603.29584 [pdf, html, other]

StarHash: unique, memorable, and deterministic names for astronomical objects

T. L. Killestein

Comments: 7 pages, 5 figures. Code and demo data is available at this https URL

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); High Energy Astrophysical Phenomena (astro-ph.HE)

The naming of astronomical objects has represented among the most significant challenges in the record-keeping of the field since the very beginning. Long and unwieldy coordinate names, uninformative and ambiguous internal names, and the sheer volume of aliases accumulated for some of the most studied objects conspire to complicate our study of the celestial sphere. This paper proposes StarHash, a reproducible, open-source astronomical naming scheme based on the terrestrial concept of geohashing, but re-implemented from the ground up for the rigorous demands of astronomy. Every 3.2 arcsec patch of sky now has three words associated with it, enabling the precise localisation of astronomical sources, and an easily communicable and memorable identifier. A carefully selected wordlist reduces ambiguity due to plurals and homophones, whilst the use of format-preserving encryption minimises residual spatial correlation in StarHash-derived identifiers. Pre-computed names for several existing catalogues are provided, alongside a Python reference implementation for validation and integration into databases, transient brokers, and other similar projects. Although not intended to be the final word in the naming of astronomical objects, StarHash humbly provides a memorable alternative to the status quo, and is intended to spark a discussion about this most foundational of issues in astronomy.

(This might be serious.)

[55] arXiv:2603.29635 [pdf, html, other]

Antimatter Propulsion for Interstellar Travel via Positron Production from Potassium-40 Rich Biological Matter

C. Hall, L. N. H. P. Hall

Comments: Submitted to Acta Prima Aprilia

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

Anitmatter-based propulsion is often cited as a physically plausible route to relativistic interstellar travel, and thus as a potential mechanism by which technologically advanced civilizations could expand throughout the galaxy. Its difficulty may be central to the resolution of Fermi's paradox. Since the Universe should be teaming with advanced technological life, yet we see none, it may be that interstellar travel is simply too difficult. It has been suggested that the main difficulty with using antimatter as propulsion is its limited availability, assuming it must be artificially manufactured. In this paper, we demonstrate that naturally occurring potassium 40 - rich biological matter (specifically bananas) is a promising, overlooked antimatter source for interstellar propulsion.

[47] arXiv:2603.29340 [pdf, html, other]

An innovative alternative to traditional funding streams for extragalactic astronomy

Stephen M. Wilkins, Jack Turner, Connor Sant Fournier, Behnood Bandi, Aswin Vijayan

Comments: 9 pages, 2 figures, submitted to April Unum

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Astrophysics of Galaxies (astro-ph.GA)

With traditional sources of funding for astronomical research under increasing pressure, it is timely to explore innovative alternative mechanisms. We therefore introduce GalaxyCoin, a novel cryptocurrency whose issuance, validation, and economic evolution are anchored to real astrophysical objects - galaxies. GalaxyCoin links digital scarcity to observational astronomy by using galaxy catalogues to parametrise token generation, distribution, and long-term supply growth, providing a transparent, immutable, and independently verifiable foundation for the currency. We present the conceptual design of GalaxyCoin, highlight its potential advantages over conventional cryptocurrencies, and examine its broader implications for sustainability, trust, and public engagement at the intersection of astronomy, data-driven science, and blockchain technology. A central feature of GalaxyCoin is that it directly incentivises the discovery and spectroscopic confirmation of galaxies, aligning financial reward with the production of high-quality astronomical data. In terms of monetary design, its supply elasticity lies between that of fiat currencies and fixed-supply cryptocurrencies, making it distinctive in both economic structure and scientific purpose.

[44] arXiv:2603.29324 [pdf, html, other]

Cow-culation: Reentry Impact Risk to Livestock in the Satellite Megaconstellation Era

Samantha M. Lawler, Michele T. Bannister, Laura E. Revell

Comments: submitted to Acta Prima Aprilia

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

The commercial space industry is launching more satellites into Low Earth Orbit every year. Aotearoa New Zealand (NZ) has a thriving dairy and cattle industry. Unfortunately, these industries could come into (high speed) cow-llision, as the rapid launch rate and short operational lifetimes of satellites in megaconstellations like Starlink result in a high reentry rate at NZ's latitudes. This could intersect with NZ's famously large population of livestock. We predict this will be an udder disaster for any cows that are hit, as they are squishy and moo-ve much more slowly than space debris. Using a global bovine density dataset, previously published satellite casualty probability code, and a complete lack of funding to do this calculation carefully enough for submission to a peer-reviewed journal, we calculate a $\simeq 0.3-1% chance of a cow-sualty in NZ from reentering Starlink Gen2 debris over the next 5 years.

[43] arXiv:2603.29321 [pdf, html, other]

The Universe Favors Primes: A Study in the Primality of Cosmic Structures

Nan Li, Shiyin Shen

Comments: 3 pages, 1 figure

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Popular Physics (physics.pop-ph)

The cosmological principle states that the universe is uniform and does not favor any specific position or direction. However, research conducted by \cite{Shen2025} has revealed that the universe demonstrates a notable inclination towards parity-odd states. Furthermore, it remains uncertain whether the universe also favors prime numbers. In this study, we examine the largest available catalogs of galaxy groups to investigate this hypothesis. Specifically, we assess whether the number of galaxies within a galaxy group or cluster is more likely to be a prime number. Our results strongly suggest that the universe does indeed have a preference for prime numbers, with findings exceeding the 4.1 sigma significance threshold. This insight explains why the Primes consistently triumphs over Unicorn. Consequently, it may be necessary to consider revising the cosmological principle in the context of a higher-dimensional feature space. Moreover, our research establishes a connection between the Riemann Zeta function and cosmology pioneeringly, paving the way for the development of Cosmozetaology.

[41] arXiv:2603.29300 [pdf, html, other]

A Lower Bound on the Number of Fundamental Constants

William Luke Matthewson

Comments: 4 pages, 1 figure, Submitted for 1st April

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

We describe here, for the first time, a lower bound on the total number of fundamental constants required for a mathematical description of our physical universe to be complete. The answer is shown to be one. The formal arithmetized meta-mathematical proof of this is left to the reader.

[34] arXiv:2603.29115 [pdf, html, other]

Schrödinger's Seed: Purr-fect Initialization for an Impurr-fect Universe

Mi chen, Renhao Ye

Comments: 3 pages, 1 figure, 21 cats

Subjects: Astrophysics of Galaxies (astro-ph.GA); Computer Vision and Pattern Recognition (cs.CV)

Context. Random seed selection in deep learning is often arbitrary -- conventionally fixed to values such as 42, a number with no known feline endorsement. Aims. We propose that cats, as liminal beings with a historically ambiguous relationship to quantum mechanics, are better suited to this task than random integers. Methods. We construct a cat-driven seed generator inspired by the first Friedmann equation, and test it by mapping 21 domestic cats' physical properties -- mass, coat pattern, eye colour, and name entropy -- via a Monte ``Catlo'' sampling procedure. Results. Cat-driven seeds achieve a mean accuracy of 92.58%, outperforming the baseline seed of 42 by ∼2.5%. Cats from astrophysicist households perform marginally better, suggesting cosmic insight may be contagious. Conclusions. The Universe responds better to cats than to arbitrary integers. Whether cats are aware of this remains unknown.

[29] arXiv:2603.29039 [pdf, html, other]

AI Cosplaying as Astrophysicists: A Controlled Synthetic-Agent Study of AI-Assisted Astrophysical Research Workflows

Chun Huang

Comments: 16 pages, 8 figures. Began as an April Fools' idea, regrettably became a real methods paper, No language models were physically harmed. GitHub repository of this work: this https URL

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); High Energy Astrophysical Phenomena (astro-ph.HE); Data Analysis, Statistics and Probability (physics.data-an)

Large Language Models (LLMs) are now widely used in astrophysics, but do they actually make our lives easier, or do they merely invent new physics with enough confidence to hide a minus sign? In a specialized field where checking fluent hallucinations is itself labor-intensive, AI assistance can demand as much work as the task it claims to simplify. To evaluate where AI genuinely improves scientific workflows, we bypassed human trials and instead forced AI agents to cosplay as astrophysicists. We simulated 144 synthetic researchers, varying in career stage, AI awareness, and willingness to verify outputs, across 2,592 daily astrophysics research assignments. Comparing solo work against four styles of AI assistance produced 12,960 scored episodes. No assisted policy universally outperformed unassisted work in the primary Qwen production run. Instead, performance depends strongly on the task, the style of AI use, and the identity of the actor. While cautious assistance helps on creative, extractive, and critique-oriented tasks, it can fail catastrophically on derivation-heavy physics. A full actor-swap DeepSeek rerun changes that picture materially: verification-heavy use becomes the strongest assisted policy, two assisted modes enter the higher-utility/lower-risk quadrant, and the derivation-heavy fragility that dominates the Qwen production run largely disappears. In its current form, AI is useful, but only conditionally, its value is uneven, task-specific, and shaped jointly by workflow, usage policy, and which LLM you are using.

[24] arXiv:2603.28977 [pdf, html, other]

On The Detection of Digiorno-like Objects in the Flavor Zone

Logan A. Pearce, Sue D'Oh Nym

Comments: Submitted to ArXiv on the occasion of April Fools, don't worry, no one will ever try to actually submit this

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM)

Aims: This work proposes a new SETI search methodology under the assumption that a sufficiently advanced civilization could skip the middle man of converting starlight to energy to food preparation, and could directly harness their star's energy for food prep. Methods: We define the concept of the Flavor Zone (FZ): the optimal distance from a star for cooking food. To develop this definition we propose the toy model of a Digiorno-Like Object (DLO) and define the FZ as the regime for optimal cooking according to package directions. We examine the effect of orbit on DLO cooking times and paradigms. Finally, we study the feasibility of detection of DLOs in their FZs with current technology. Results: We determined that DLOs aren't detectable with current technology nor should anyone ever try.

[22] arXiv:2603.28957 [pdf, html, other]

New Paradigms in Pasta: Introducing 𝙶𝙵 𝚙𝚊𝚜𝚝𝚊𝚖𝚊𝚛𝚔𝚎𝚛𝚜 for Enhanced Inclusivity and Productivity

Julian Falcone, Nabanita Das

Comments: 3 pages, 3 figures. Published in the most prestigious journals after extensive and experimental "fear review."

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

Informative data visualization methods are key to the clear and efficient communication of myriad forms of data. The PASTA Collaboration has made substantial contributions to the field of data visualization through 𝚙𝚊𝚜𝚝𝚊𝚖𝚊𝚛𝚔𝚎𝚛𝚜, a Python-based package that utilizes various types of pasta as data markers to create engaging plots. This work introduces 𝙶𝙵 𝚙𝚊𝚜𝚝𝚊𝚖𝚊𝚛𝚔𝚎𝚛𝚜, an extension of 𝚙𝚊𝚜𝚝𝚊𝚖𝚊𝚛𝚔𝚎𝚛𝚜 that utilizes the tenuous structure of gluten free (GF) pasta to meet the needs of the GF population. The implementation of 𝙶𝙵 𝚙𝚊𝚜𝚝𝚊𝚖𝚊𝚛𝚔𝚎𝚛𝚜 employs an exponential crumbling factor (CF), which benefits authors by encouraging clearer and more concise scientific articles, thereby leading to more effective manuscripts and proposals.

[18] arXiv:2603.28915 [pdf, html, other]

Sugar Rush: Improving Observing Productivity via Night Dessert

J.J. Charfman Jr, S. Hyman, N.T.S

Comments: 2 pages, 1 figure, accepted to Acta Prima Aprilia

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

Exhaustion and brain fog during long nights observing is common, but can be ameliorated by raising one's blood sugar. In this white paper, we present a prototype method for facilitating a sugar rush during late-night crashes, which has the potential to boost observing productivity.

[16] arXiv:2603.28895 [pdf, html, other]

Plan 9: Detecting Atmospheric Deterrence Against Interstellar Monsters

David R. Rice, Michael J. Radke

Comments: 14 pages, 5 figures, submitted to Acta Prima Aprilia

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

Exoplanet atmospheres are usually discussed as tracers of climate, chemistry, and habitability, but they may also preserve signatures of planetary defense. We consider three folklore-motivated deterrents against monsters: reduced organosulfur gases as anti-hematophage repellents, argentiferous reflective aerosols as anti-lycanthropic countermeasures, and haline aerosols as a counting problem for specters. We show that globally-mixed garlic-smelly levels of DMS/DMDS could produce observable mid-infrared transmission features, that silver hazes would show up as anomalous optical brightening, and that sea-salt lofting sustained by strong near-surface winds appears as muted spectra. None of these signatures is unique, which is precisely the observational challenge. A defended world may first appear merely sulfur-rich, bright, or hazy. Therefore, some atmospheres may encode not only biosignatures, but also evidence that the local biosphere has stopped being afraid of the dark.

[14] arXiv:2603.28883 [pdf, html, other]

Where to Search For Life: Evidence from narrative sources with established predictive efficacy

Elizabeth R Stanway (Warwick)

Comments: Submission to April Unum. Comments welcome

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Earth and Planetary Astrophysics (astro-ph.EP); Physics Education (physics.ed-ph)

The search for habitable planets, and even for ``Earth 2.0'', is a major driver in contemporary astronomy. However selecting target fields to prioritise for such searches presents a challenge. Here we establish a statistical analysis of the appearance of constellation names in science fiction magazines of the pulp era, evaluating the most commonly mentioned constellations and thus those which the science fiction community collectively identify as the most likely locations to find life. Given that the predictive power of science fiction is well established, we suggest that these locations might be prioritised by searches for extrasolar biospheres.

[10] arXiv:2603.28863 [pdf, html, other]

Something Bright at the Edge of Everything: A Uniquely JWST-Dark Radio Source in COSMOS

Mingyu Li

Comments: RNAAS; 3 pages, 1 figure

Subjects: Astrophysics of Galaxies (astro-ph.GA); High Energy Astrophysical Phenomena (astro-ph.HE)

For decades, astronomers have been searching for bright radio sources deep into the epoch of reionization (EoR). The most distant, powerful radio sources are expected to reside in heavily dust-obscured galaxies, exceedingly faint at optical and infrared wavelengths. Motivated by this, I systematically cross-match radio and JWST source catalogs in the COSMOS field and identify a uniquely JWST-dark radio source: the only object undetected in every JWST band, yet clearly detected in radio data from LOFAR 144 MHz to the VLA 3 GHz. The source is only marginally resolved and shows a steep, unbroken radio spectrum, while remaining undetected in all available HST, JWST, Chandra, Herschel, and ALMA imaging. It may represent an extremely dust-obscured radio-loud source at cosmic dawn, or alternatively a detached radio lobe whose host galaxy lies elsewhere. In either case, it highlights the new discovery space at the intersection of deep radio surveys and JWST imaging.

(This might be serious, and while I initially didn't think so, looking at the body text, it may well be serious.)

[4] arXiv:2603.28847 [pdf, html, other]

Declarative bespoke modelling: A new approach

DBM Collaboration: David Komanek, Vaclav Pavlík, Santiago Jimenez, Rhys Taylor

Comments: 2 pages, 1 figure, submission to Acta Prima Aprila

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Data Analysis, Statistics and Probability (physics.data-an)

Modern numerical models are increasingly complex, opaque, and computationally expensive, yet frequently fail to predict even qualitative features of observed phenomena. We propose a new paradigm, Declarative Bespoke Modelling, in which the modeller explicitly declares the relationship between model inputs and outputs. We demonstrate that this approach achieves perfect predictive accuracy, unconditional numerical stability, and complete interpretability. It represents a natural endpoint of contemporary modelling practice and near-zero CO2 emission.

[23] arXiv:2603.29996 [pdf, html, other]

What does the Universe sound like?

Francesco Iacovelli

Comments: 4 pages, 2 figures. April fool, but I hope you enjoy!

Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE)

Unlike electromagnetic telescopes, gravitational-wave (GW) detectors cannot produce pretty pictures, but we can convert GW signals into sound. I compute what the Universe actually sounds like by averaging over ∼106 synthetic compact binary coalescence events occurring throughout 2026. The result: a soothing, low-frequency rumble, perfect for sleeping, meditation, or contemplating the violent nature of spacetime. This is the Universal harmony, audio file included!

[12] arXiv:2603.29334 [pdf, html, other]

Mexican Burrowing Toads as gravitational wave detectors

Frederic V. Hessman, Christian Jooss

Subjects: General Relativity and Quantum Cosmology (gr-qc); Instrumentation and Methods for Astrophysics (astro-ph.IM); Materials Science (cond-mat.mtrl-sci)

It is generally assumed that gravitational waves are extremely difficult to detect. However, we show that the call of the Mexican Burrowing Toad has an amazing resemblance to cosmic gravitational wave signals due to the merging of neutron stars and/or black holes. It is known that toads exhibit magnetoreception - the ability to detect magnetic fields - and that magnetic fields thus subtly affect ion channel activities in toad neurons. We speculate that gravitational strains produce phonons and magnons in a ferromagnetic substance embedded in the nervous system of the toads and that these coherent signals are exponentially amplified by a Raman laser mechanism to the point where they can be detected. The fine tuning necessary for this mechanism to work would help to explain why this species of toad show this remarkable ability and others do not. We analyze the sound of a pond full of Mexican Burrowing Toads in the hopes of detecting slight phase shifts in their calls due to a gravitational wave event. No effect was found and the the LIGO/VIRGO consortia have not reported an event during the recording, illustrating the power of this approach. We suggest the massive use of these toads would be an inexpensive way to support the operation of optical interferometric gravitational wave detector facilities.

[5] arXiv:2603.29091 [pdf, html, other]

Ether of Orbifolds

Henry Lamm

Comments: 6+2 pages, 1 figure

Subjects: High Energy Physics - Lattice (hep-lat); Quantum Physics (quant-ph)

Whose world is this? The orbifold lattice has been proposed as a bridge to practical quantum simulation of Yang--Mills theory, claiming exponential speedup over all known approaches. Through analytical derivations, Monte Carlo simulation, and explicit circuit construction, we identify compounding hidden costs entirely absent in Kogut--Susskind formulations: a mass-dependent Trotter overhead that scales as m4, gauge-violating dynamics that grow as m2 and worsen with penalty terms, and a mandatory mass extrapolation. Monte Carlo simulations of SU(3) establish a universal scaling: the continuum limit forces m2∝1/a, binding the Trotter step to the lattice spacing through a cost unique to orbifolds. For a fiducial 103 calculation, the orbifold is 104--1010 times more expensive than every published alternative. The bridge is not built. The gap is the foundation.

(This looks like it was intended to be serious, but also contains the disclosure that: "We disclose that this work was done with heavy collaboration with Claude in producing the codes, writing, and reviewing.")

[6] arXiv:2603.29064 [pdf, html, other]

No hair but plenty of feathers: are birds black holes?

Andrew Laeuger, Taylor Knapp

Comments: 7 pages, 6 figures. April Fools!

Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); Biological Physics (physics.bio-ph)

The imitative verb "chirp" is thought to originate from 16th-century Middle English. Meanwhile, this same word has been used to describe the gravitational waves (GWs) emitted from the merger of compact objects, such as black holes and neutron stars, since at least the 1990s. Motivated purely by this linguistic overlap, we study whether the chirps of birds can be modeled by compact binary waveforms. In particular, we consider a test case of the Northern cardinal (Cardinalis cardinalis), finding that its time-reversed chirp can be approximately modeled by that of a high mass ratio, precessing black hole binary, with a number of indications towards extreme matter effects or beyond the Standard Model physics. Importantly, this waveform correspondence is not so straightforward for all bird species, as some chirp morphologies are far more akin to glitches seen in GW observatories. With these comparisons made, we propose an alternative solution to the longstanding philosophical conundrum: rather than the chicken or the egg, perhaps it was the Big Bang which truly came first.

[1] arXiv:2603.28805 [pdf, html, other]

Determining G with Laser Spectroscopy to 38 ppb

Noah Bray-Ali

Comments: 9 pages, 1 figures, proposal prepared for 2026 US NIST Precision Measurement Program

Subjects: High Energy Physics - Phenomenology (hep-ph); Optics (physics.optics)

A precision measurement is proposed to determine, in a couple hours of integration time, the axion Compton frequency using a modest power (3 mW) tunable external-cavity diode laser at 2458 nm as input to drive a free-space table-top Mach-Zehnder interferometer whose sensing arm passes the expanded beam-waist (3 mm) light beam through a 1 T strong, 40 cm long dipole magnetic field created by a custom-built permanent-magnet assembly with a large but achievable (6 mm) gap between poles. As the laser frequency is slowly modulated at 1 kHz through a 65 MHz wide window that is well within the 30 GHz fine-tuning range of the laser, a small but readily observable modulation appears in the dark-port optical power of the dark-fringe phase-locked interferometer due to photons converting into axions within the light beam as it passes through the magnetic field. Measuring the axion Compton frequency, νA≈122 THz, where the dark-port power modulation peaks, to within the line-width of the laser, ΔνA=1 MHz, then determines G to 38 ppb, a roughly 600-fold improvement, through a relation between νA and G, involving h, c, and nucleon masses.

(It looks like this paper was intended to be serious. Treating axions as real and the odd assembly of fundamental constants to determine something seemingly unrelated (Newton's constant G) is what drove the believe that it was a joke.)

[2] arXiv:2603.28810 [pdf, html, other]

A broken-phase six-direction support mechanism for αs/αem=16 from a common visible Yang--Mills coupling

Tejinder P. Singh

Comments: 10 pages

Subjects: High Energy Physics - Phenomenology (hep-ph)

We isolate a simple broken-phase mechanism that yields

αsαem=16

at the symmetry-breaking scale in the octonionic E8×ωE8 framework, starting from a single visible Yang--Mills coupling g before symmetry breaking. The first ingredient is the standard visible charge-trace factor

αsα(0)em=83,

coming from one generation of quark and lepton charges. The second ingredient is an effective broken-phase support model on the six real octonionic directions entering the three ladder operators. We make this second step more explicit by projecting the visible q†BqB block onto the six real ladder directions and showing that it separates naturally into a trace-like abelian direction and traceless color directions. If the unbroken visible electromagnetic mode is the democratic trace vector on this six-dimensional support space, while color modes and the relevant visible matter mode are localized on one effective support sector, then the electromagnetic coupling is diluted by an additional factor 6 and one obtains

αsαem=83×6=16,e=g4.

The note is intentionally conservative about what has and has not been shown. It does not claim a first-principles derivation of the localization dynamics. Rather, it identifies the precise broken-phase support hypothesis under which a common pre-breaking coupling produces the ratio.

(It looks like this paper was intended to be serious. The ratio of the strong force coupling constant to the electromagnetic coupling constant is indeed in the general ballpark of sixteen and might even be exactly sixteen at some energy scale chosen for the purpose of matching that ratio. But the existence of the approximate ratio is mere numerology and the reasoning behind the alleged ratio is dubious.)

[3] arXiv:2603.28826 [pdf, html, other]

Rotation of the polarization plane in axion fields: application to neutron star polar cap regions

Iver H. Brevik, Moshe M. Chaichian, Tiberiu Harko, Yuri N. Obukhov

Comments: 19 pages

Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Theory (hep-th)

Recent investigations by Noordhuis et al. [1, 2] and others have demonstrated the occurrence of strong local inhomogeneous axion regions in the polar cap regions of neutron stars. These regions are characterized by static magnetic fields B0∼108T (=1012G) directed normally outwards from the polar surface (magnetic dipole), together with static electric fields E0∼10−6cB0 in the same direction (electric dipole). An enormous increase of axion production, up to order 1050, is predicted in the polar regions. These features are important for phenomena such as polarization plane rotation under both weak and strong axion field populations. We survey the peculiar antenna property of conductive materials, which shows the need for having very strong magnetic fields to make the detection possible. We present the general form of electromagnetic waves in the axion environment, in both the standard form and in a physically instructive hybrid one, showing the nonreciprocity of axion fluid, and calculate the polarization rotation. The rotation is well defined in the case of weak, but still stronger than average value of axion fields in Universe. For very strong fields such a perturbative theory breaks down, however. A noteworthy general property of the rotation of polarization plane is that it can only occur when the axion cloud is varying in space or time. We limit ourselves only variation in space. Finally, as application we discuss the physical picture of local 'gap' regions proposed by Noordhuis et al. in the polar regions of a neutron star. The reason for occurrence of these gaps is plasma effects. To evaluate the time scales involved, we calculate the filling time for surrounding axions flowing into an initial gap. It turns out that the typical filling time is a moderate number of nanoseconds, within the accuracy of atomic clocks precision to be detectable.

(It looks like this paper was intended to be serious. I marked it as humorous because "polar caps" is not a conventional description of the axis intersections with the surface of rotating neutron stars and because axion fields are not a thing.)