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Establishing a unified theory of cognition has been a major goal of psychology. While there have been previous attempts to instantiate such theories by building computational models, we currently do not have one model that captures the human mind in its entirety. Here we introduce Centaur, a computational model that can predict and simulate human behavior in any experiment expressible in natural language. We derived Centaur by finetuning a state-of-the-art language model on a novel, large-scale data set called Psych-101. Psych-101 reaches an unprecedented scale, covering trial-by-trial data from over 60,000 participants performing over 10,000,000 choices in 160 experiments. Centaur not only captures the behavior of held-out participants better than existing cognitive models, but also generalizes to new cover stories, structural task modifications, and entirely new domains. Furthermore, we find that the model's internal representations become more aligned with human neural activity after finetuning. Taken together, Centaur is the first real candidate for a unified model of human cognition. We anticipate that it will have a disruptive impact on the cognitive sciences, challenging the existing paradigm for developing computational models.

There are many ways to embed the Lie groups of the Standard Model of Particle Physics in a Lie group of type $E_8$, but so far there is no convincing demonstration that the finite symmetries (and asymmetries) of weak hypercharge, three generations of electrons, three quarks in a proton, and photon polarisation can also be embedded correctly. I show that there is a unique way to embed these finite symmetries consistently, and that the gauge groups of the Standard Model are then uniquely determined. The model is automatically chiral, and the generation symmetry acts as a rotation in a real 2-space, so that the spinors for three generations have only twice as many degrees of freedom in total as the spinors for a single generation. In fact, two distinct generation symmetries arise from the restriction to the Standard Model, related by the CKM and/or PMNS matrices. It therefore appears that these two matrices are not independent. I further speculate on the implications for quantum gravity., Comment: 27 pages. Additional sections on the possibility of using triality to relate the Pati-Salam model to general relativity

The Submillimeter Array (SMA) is an array of 8 antennas operating at millimeter and submillimeter wavelengths on Maunakea, Hawaii, operated by the Smithsonian Astrophysical Observatory and Academia Sinica Institute of Astronomy and Astrophysics, Taiwan. Over the past several years, we have been preparing a major upgrade to the SMA that will replace the aging original receiver cryostats and receiver cartridges with all new cryostats and new 230 and 345 GHz receiver designs. This wideband upgrade (wSMA) will also include significantly increased instantaneous bandwidth, improved sensitivity, and greater capabilities for dual frequency observations. In this paper, we will describe the wSMA receiver upgrade and status, as well as the future upgrades that will be enabled by the deployment of the wSMA receivers., Comment: To be published in the proceedings of SPIE Astronomical Telescopes + Instrumentation 2024, paper number 13096-122

I investigate the structure of $E_8$ under the action of the subalgebra/subgroup $A_1+G_2+C_3$, as a potential route to unification of the fundamental forces of nature into a single algebraic structure. The particular real form $E_{8(-24)}$ supports a decomposition into compact $G_2$ plus split $A_1+C_3$, which allows a restriction from $G_2$ to $SU(3)$ for the strong force, together with split $SL_2(\mathbb R)$ to break the symmetry of the weak interaction and give mass to the intermediate vector bosons. The factor $C_3$ contains various copies of the Lorentz group $SL_2(\mathbb C)$ and extends the `spacetime' symmetries to the full group of symplectic symmetries of real $3+3$-dimensional phase space. Restricting $G_2$ to the Standard Model $SU(3)$ extends $C_3$ to $A_5$, in the real form $SU(3,3)$, acting on a complex phase space that includes both momentum and current. There is then a natural restriction from $SU(3,3)$ to $SO(3,3)$, describing the action of $SL_4(\mathbb R)$ on phase space. The resulting action of $SL_4(\mathbb R)$ on $E_8$ includes tensors that are equivalent to the stress-energy tensor, the Ricci tensor and the Riemann tensor, and therefore permits the formalism of general relativity to be developed inside $E_{8(-24)}$. The model then suggests unexpected and perhaps subtle ways in which general relativity and particle physics may be forced to modify each other, in order to produce a unified theory., Comment: 18 pages. v2: extended the discussion of gravity, revised the title and abstract accordingly

I show how the isomorphism between the Lie groups of types $B_2$ and $C_2$ leads to a faithful action of the Clifford algebra $\mathcal C\ell(3,2)$ on the phase space of 2-dimensional dynamics, and hence to a mapping from Dirac spinors modulo scalars into this same phase space. Extending to the phase space of 3-dimensional dynamics allows one to embed all the gauge groups of the Standard Model as well, and hence unify the electro-weak and strong forces into a single algebraic structure, identified as the gauge group of Hamiltonian dynamics. The gauge group transforms between phase space coordinates appropriate for arbitrary observers, and therefore shows how the apparently arbitrary parameters of the Standard Model transform between mutually accelerating observers. In particular, it is possible to calculate the transformation between an inertial frame and the laboratory frame, in order to explain how macroscopic laboratory mechanics emerges from quantum mechanics, and to show how to write down a quantum theory of gravity that is consistent with quantum mechanics, but is not consistent with General Relativity.

I propose a discrete model for the Gell-Mann matrices, which allows them to participate in discrete symmetries of three generations of four types of elementary fermions, in addition to their usual role in describing a continuous group $SU(3)$ of colour symmetries. This model sheds new light on the mathematical (rather than physical) necessity for `mixing' between the various gauge groups $SU(3)$, $SU(2)$ and $U(1)$ of the Standard Model. In particular it shows how the anti-Hermitian version of Pauli matrices can act non-trivially on a unitary version of the Gell-Mann matrices, which leads to a non-trivial mixing between the weak and strong nuclear forces. The unitary version of the Gell-Mann matrices can in turn act non-trivially on a quaternionic version of Dirac matrices, which leads to a non-trivial mixing between the strong force and the shape of spacetime defined by the Dirac matrices. Hence this model implies a mixing between the electro-weak-strong forces on the one hand and gravity, as described by General Relativity, on the other. This mixing in turn implies the necessity for both general relativistic corrections to the Standard Model of Particle Physics, and quantum corrections to General Relativity. Contrary to general expectation, both types of corrections seem to be large enough to be tested experimentally., Comment: New sections on action of Gell-Mann matrices on Dirac matrices, and potential implications for quantum gravity. Now 35 pages

We decompose the Lie algebra $\mathfrak{e}_{8(-24)}$ into representations of $\mathfrak{e}_{7(-25)}\oplus\mathfrak{sl}(2,\mathbb{R})$ using our recent description of $\mathfrak{e}_8$ in terms of (generalized) $3\times3$ matrices over pairs of division algebras. Freudenthal's description of both $\mathfrak{e}_7$ and its minimal representation are therefore realized explicitly within $\mathfrak{e}_8$, with the action given by the (generalized) matrix commutator in $\mathfrak{e}_8$, and with a natural parameterization using division algebras. Along the way, we show how to implement standard operations on the Albert algebra such as trace of the Jordan product, the Freudenthal product, and the determinant, all using commutators in $\mathfrak{e}_8$., Comment: 11 pages

We describe computer calculations that were used in 2016 to classify subgroups of the Monster isomorphic to $PSL_2(8)$, containing $7B$-elements. It turns out that there is no such $PSL_2(8)$ in the Monster. These calculations confirm earlier unpublished calculations by P. E. Holmes that obtained the same result. The result has also been confirmed in independent calculations by H. Dietrich, M. Lee and T. Popiel, using different software by M. Seysen. Thus this experimental result is shown to be reproducible.

We construct the well-known decomposition of the Lie algebra $\mathfrak{e}_8$ into representations of $\mathfrak{e}_6\oplus\mathfrak{su}(3)$ using explicit matrix representations over pairs of division algebras. The minimal representation of $\mathfrak{e}_6$, namely the Albert algebra, is thus realized explicitly within $\mathfrak{e}_8$, with the action given by the matrix commutator in $\mathfrak{e}_8$, and with a natural parameterization using division algebras. Each resulting copy of the Albert algebra consists of anti-Hermitian matrices in $\mathfrak{e}_8$, labeled by imaginary (split) octonions. Our formalism naturally extends from the Lie algebra to the Lie group $E_6\subset E_8$., Comment: 9 pages

As was discovered with other wide field, precise imagers, the stable photometry necessary for the microlensing surveys is well-suited to general stellar astrophysics, including stellar flares, which are important for understanding stellar magnetic activity and even the space weather environments of exoplanets. Large stellar flare surveys have never been performed before in the Roman spectral range, and Roman may reveal new information about flare emission mechanisms (blackbody, recombination continuum, chromospheric emission lines) and how flare rates change with stellar age and metallicity. For instance, the Galactic Bulge stars will be much older than the typical studied flare stars, and Roman's wide field and exquisite imaging may provide sufficient statistics to probe the flare behavior and properties of such an old stellar population. However, the information yield will likely depend on sky location, cadence, read-out strategy, and filter choices. Stellar flare timescales range from seconds to hours, so Roman may only be able to resolve the longest, most energetic events. However, because a single exposure in the Galactic Bulge Time Domain Survey will consist of several non-destructive reads, short duration events can be modeled from the flux variations within a single exposure. Here we provide a proof of concept, showing that flare morphologies can be significantly better constrained if sub-exposure data are analyzed. As a result, we advocate that such data be made publicly available for Roman flare studies, with minimal on-board processing., Comment: Roman Core Community Survey White Paper, 6 pages, 2 figures

Despite multiple previous searches, no transiting planets have yet been identified within a globular cluster. This is believed to be due to a combination of factors: the low metallicities of most globular clusters suggests that there is significantly less planet-forming material per star in most globular clusters relative to the solar neighborhood, the high likelihood of dynamical interactions can also disrupt planetary orbits, and the data available for globular clusters is limited. However, transiting planets have been identified in open clusters, indicating that there may be planets in more massive clusters that have simply gone undetected, or that more massive clusters inhibit planet formation. Less than two degrees away from the nominal Galactic Bulge Time Domain Survey footprint, two globular clusters, NGC 6522 and NGC 6528, can be simultaneously observed by the Roman telescope during the Galactic Bulge Time Domain Survey. These clusters are comparable in mass (1-2 x 10$^5$ solar masses) and age (12 Gyr), but feature drastically different average metallicities: NGC 6522 has an average [Fe/H] $\sim$ -1.3, while NGC 6528 has an average [Fe/H] $\sim$ -0.1. If no transiting planets are detected in one season of time domain observations of these clusters, this would indicate a difference in planet occurrence among field stars and globular clusters at >3-$\sigma$ significance even after accounting for metallicity, which could be enhanced to >5-$\sigma$ significance with similar observations of another nearby field hosting a metal-rich globular cluster. Additionally, time domain observations of NGC 6522 and NGC 6528 will detect variable stars in both clusters, testing the connection between stellar variability and binary fraction to metallicity and cluster environment, as well as testing the dependence of exoplanet yields on stellar density and distance from the Galactic midplane., Comment: 7 pages, 3 figures

In this White Paper for Nancy Grace Roman Space Telescope (Roman) science, we propose the Roman Survey of the Earth Transit Zone (RoSETZ), a transit search for rocky planets within the habitable zones (HZs) of stars located within the Earth Transit Zone (ETZ). The ETZ holds special interest in the search for extra-terrestrial intelligence (SETI) - observers on planets within the ETZ can see Earth as a transiting planet. RoSETZ would augment the Roman Galactic Bulge Time Domain Survey (GBTDS) as an additional field located $\sim 5$~degrees away from other GBTDS fields. Our simulations show that RoSETZ alone can find from 120 to 630 Earth-sized HZ planets around K- and M-type hosts, with the range reflecting different survey design assumptions. These yields are 5-20 times the number currently known. Such a sample will transform our knowledge of ``Eta-Earth'' ($\eta_{\oplus}$) -- the occurrence of Earth-sized HZ planets -- and would be the first catalogue of exoplanets selected in a manner optimized according to the Mutual Detectability targetted-SETI strategy. If it can be accommodated alongside the existing GBTDS design, we favour a RoSETZ-Max design that is observed for the duration of the GBTDS. If not, we show that a slimmed-down RoSETZ-Lite design, occupying two GBTDS seasons, would not significantly impact overall GBTDS exoplanet yields, even if time allocated to it had to come from time allocations to other fields. We argue that the angular separation of RoSETZ from other GBTDS fields permits self-calibration of systematic uncertainties that would otherwise hamper exoplanet demographic modelling of both microlensing and transit datasets. Other science possible with RoSETZ data include studies of small solar system bodies and high resolution 3D extinction mapping., Comment: 20 pages. Submission to the NASA Roman Core Community Surveys White Paper Call

The Nancy Grace Roman Space Telescope (Roman) is NASA's next astrophysics flagship mission, expected to launch in late 2026. As one of Roman's core community science surveys, the Galactic Bulge Time Domain Survey (GBTDS) will collect photometric and astrometric data for over 100 million stars in the Galactic bulge to search for microlensing planets. To assess the potential with which Roman can detect exoplanets via transit, we developed and conducted pixel-level simulations of transiting planets in the GBTDS. From these simulations, we predict that Roman will find between $\sim$60,000 and $\sim$200,000 transiting planets, over an order of magnitude more planets than are currently known. While the majority of these planets will be giants ($R_p>4R_\oplus$) on close-in orbits ($a<0.3$ au), the yield also includes between $\sim$7,000 and $\sim$12,000 small planets ($R_p<4 R_\oplus$). The yield for small planets depends sensitively on the observing cadence and season duration, with variations on the order of $\sim$10-20% for modest changes in either parameter, but is generally insensitive to the trade between surveyed area and cadence given constant slew/settle times. These predictions depend sensitively on the Milky Way's metallicity distribution function, highlighting an opportunity to significantly advance our understanding of exoplanet demographics, particularly across stellar populations and Galactic environments., Comment: Accepted to ApJS; 64 pages, 18 figures

We report the detection and validation of two planets orbiting TOI-2095 (TIC 235678745). The host star is a 3700K M1V dwarf with a high proper motion. The star lies at a distance of 42 pc in a sparsely populated portion of the sky and is bright in the infrared (K=9). With data from 24 Sectors of observation during TESS's Cycles 2 and 4, TOI-2095 exhibits two sets of transits associated with super-Earth-sized planets. The planets have orbital periods of 17.7 days and 28.2 days and radii of 1.30 and 1.39 Earth radii, respectively. Archival data, preliminary follow-up observations, and vetting analyses support the planetary interpretation of the detected transit signals. The pair of planets have estimated equilibrium temperatures of approximately 400 K, with stellar insolations of 3.23 and 1.73 times that of Earth, placing them in the Venus zone. The planets also lie in a radius regime signaling the transition between rock-dominated and volatile-rich compositions. They are thus prime targets for follow-up mass measurements to better understand the properties of warm, transition radius planets. The relatively long orbital periods of these two planets provide crucial data that can help shed light on the processes that shape the composition of small planets orbiting M dwarfs., Comment: Submitted to AAS Journals

I show how the symmetry-breaking of a recently proposed embedding of the standard model of particle physics in $E_8$ can be explained in terms of the representation theory of the binary tetrahedral group. This finite group provides a link between various types of spin and isospin that can be exploited to `explain' the chirality of the weak interaction, and the existence of three generations of fermions. Two apparently small technical differences between the finite group model and the standard model turn out to have profound consequences for the ways in which the weak and strong forces create mass., Comment: 15 pages

We show how chirality emerges naturally from an embedding of the standard model of particle physics into $E_{8(-24)}$. The well-known argument that there is no chiral theory of fundamental physics in $E_8$ is avoided by implementing chirality not as a property of the complexified Lorentz group, but as a property of the complex representations of the real Lorentz group, combined with a real scalar. This avoids the problems of complexification, and ensures that the model is completely contained in the real Lie group.

I propose the group SL(4,R) as a generalisation of the Dirac group SL(2,C) used in quantum mechanics, as a possible basis on which to build a more general theory from which the standard model of particle physics might be derived as an approximation in an appropriate limit., Comment: This is a preprint version of an article accepted for publication in the International Journal of Geometrical Methods in Modern Physics

The concept of mass was introduced as a mathematical abstraction and unifying principle in physics by Newton in the 17th century, and calibrated on a Solar System scale by Cavendish at the end of the 18th century. In the 19th century, this concept proved adequate to explain a vast range of physical processes on all scales from the microscopic to the Solar System. But in the 20th century, attempts to extend this range upwards to the galactic scale, and downwards to subatomic particles, have led to increasing difficulties. Modifications to the concept of mass by Einstein and Dirac have not prevented these difficulties. In this paper, I ask the question, can these difficulties be overcome by further modification of the definitions, or is the concept of mass an unavoidably local (Solar System scale) rather than global concept?, Comment: Now 7 pages; [v2] added discussion of the mass ratios of the three generations of electron; re-written conclusions; [v3] corrected statistical estimates; [v4] simplified the argument and addressed comments from referees and others

The recently reported $7\sigma$ anomaly in measurements of the W/Z mass ratio, if confirmed, will demand an extension of some kind to the standard model of particle physics. In this paper I consider whether some recently proposed models are capable, in principle, of resolving this anomaly, subject to experimental confirmation.

We interpret the elements of the exceptional Lie algebra $\mathfrak{e}_{8(-24)}$ as objects in the Standard Model, including lepton and quark spinors with the usual properties, the Standard Model Lie algebra $\mathfrak{su}(3)+\mathfrak{su}(2)+\mathfrak{u}(1)$, and the Lorentz Lie algebra $\mathfrak{so}(3,1)$. Our construction relies on identifying a complex structure on spinors and then working in the enveloping algebra. The resulting model naturally contains GUTs based on $SO(10)$ (Georgi--Glashow), $SU(5)$ (Georgi), and $SU(4)\times SU(2)\times SU(2)$ (Pati--Salam). We then briefly speculate on the role of the remaining elements of $\mathfrak{e}_8$, and propose a mechanism leading to exactly three generations of particles., Comment: 15 pages; to appear in J. Math. Phys

This Snowmass 2021 White Paper describes the Cosmic Microwave Background Stage 4 project CMB-S4, which is designed to cross critical thresholds in our understanding of the origin and evolution of the Universe, from the highest energies at the dawn of time through the growth of structure to the present day. We provide an overview of the science case, the technical design, and project plan., Comment: Contribution to Snowmass 2021. arXiv admin note: substantial text overlap with arXiv:1908.01062, arXiv:1907.04473

This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library (MaStar) accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) survey which publicly releases infra-red spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the sub-survey Time Domain Spectroscopic Survey (TDSS) data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey (SPIDERS) sub-survey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated Value Added Catalogs (VACs). This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper (MWM), Local Volume Mapper (LVM) and Black Hole Mapper (BHM) surveys., Comment: 40 pages, 8 figures, 6 tables. In press at ApJSS (arxiv v2 corrects some minor typos and updates references)