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Massless chiral excitations can arise from the interactions between a fermion and an axion string, propagating along the string and allowing it to superconduct. The properties of these excitations, or zero modes, dictate how the string interacts with light and can thus have important phenomenological consequences. In this paper, we add a nowhere-vanishing Dirac mass for the fermion in the usual model of axion electrodynamics. We find that the zero modes exhibit an interesting phase structure in which they delocalize from the string’s core as the mass increases, up until a critical value past which they disappear. We study this structure from an analytic perspective, with explicit numerical solutions, and via anomaly inflow arguments. Finally, we derive the two-dimensional effective theory of the zero mode and its interactions with the four-dimensional gauge field and show how this effective theory breaks down as the zero modes delocalize. [ABSTRACT FROM AUTHOR]

We study the dynamics of scalar fields with compact field spaces, or axions, in de Sitter space. We argue that the field space topology can qualitatively affect the physics of these fields beyond just which terms are allowed in their actions. We argue that the sharpest difference is for massless fields — the free massless noncompact scalar field does not admit a two-point function that is both de Sitter-invariant and well-behaved at long distances, while the massless compact scalar does. As proof that this difference can be observable, we show that the long-distance behavior of a heavy scalar field, and thus its cosmological collider signal, can qualitatively change depending on whether it interacts with a light compact or noncompact scalar field. We find an interesting interplay between the circumference of the field space and the Hubble scale. When the field space is much larger than Hubble, the compact field behaves similarly to a light noncompact field and forces the heavy field to dilute much faster than any free field can. However, depending on how much smaller the field space is compared to Hubble, the compact field can cause the heavy scalar to decay either faster or slower than any free field and so we conclude that there can be qualitative and observable consequences of the field space's topology in inflationary correlation functions. [ABSTRACT FROM AUTHOR]

We study the self-energies of weakly interacting scalar fields in de Sitter space with one field much lighter than the Hubble scale. We argue that self-energies drastically simplify in this light limit. We illustrate this in theories with two scalar fields, one heavy and one light, interacting with one another through either cubic or quartic interactions. To regulate infrared divergences, we compute these self-energies in Euclidean de Sitter space and then carefully analytically continue to Lorentzian signature. In particular, we do this for the most general renormalizable theory of two scalar fields with even interactions to leading order in the coupling and the mass of the light field. These self-energies are determined by de Sitter sunset diagrams, whose analytic structure and UV divergences we derive. Even at very weak couplings, the light field can substantially change how the heavy field propagates over long distances. The light field’s existence may then be inferred from how it modifies the heavy field’s oscillatory contribution to the primordial bispectrum in the squeezed limit, i.e. its cosmological collider signal. [ABSTRACT FROM AUTHOR]

When faced with difficult choices, the possible outcomes are considered through a process known as deliberation. In rats, deliberation is thought to be reflected by pause-and-reorienting behaviors, better known as vicarious trial and errors (VTEs). While VTEs are thought to require medial prefrontal cortex (mPFC) and dorsal hippocampal (dHPC) interactions, no empirical evidence has yet demonstrated such a dual requirement. The nucleus reuniens (Re) of the ventral midline thalamus is anatomically connected with both the mPFC and dHPC, is required for HPC-dependent spatial memory tasks, and is critical for mPFC-dHPC neural synchronization. Currently, it is unclear if, or how, the Re is involved in deliberation. Therefore, by examining the role of the Re on VTE behaviors, we can better understand the anatomical and physiological mechanisms supporting deliberation. Here, we examined the impact of Re suppression on VTE behaviors and mPFC-dHPC theta synchrony during asymptotic performance of a HPC-dependent delayed alternation (DA) task. Pharmacological suppression of the Re increased VTE behaviors that occurred with repetitive choice errors. These errors were best characterized as perseverative behaviors, in which some rats repeatedly selected a goal arm that previously yielded no reward. We then examined the impact of Re suppression on mPFC-dHPC theta synchrony during VTEs. We found that during VTEs, Re inactivation was associated with a reduction in mPFC-dHPC theta coherence and mPFC-to-dHPC theta directionality. Our findings suggest that the Re contributes to deliberation by coordinating mPFC-dHPC neural interactions. [ABSTRACT FROM AUTHOR]

A central object in any axionic theory is its periodic potential, which is typically generated by instantons. The goal of this paper is to understand what physically happens to the theory when we lose control of the potential's instanton expansion. We argue, using the Yang-Lee theory of phase transitions, that the theory breaks down in the classic sense: states become light. However, these states are not necessarily light for all values of the axion and there can be large regions where the effective description remains valid. We find alternative expressions for the effective potential in terms of the properties of these light states, which remain useful even when the instanton expansion breaks down, and thus initiate a push beyond the lamppost of large instanton actions. Most of these questions are motivated by the axionic Weak Gravity Conjecture, which we reformulate without reference to instanton actions. We also comment on its ability to constrain large-field axion inflation. [ABSTRACT FROM AUTHOR]

We develop methods for resummation of instanton lattice series. Using these tools, we investigate the consequences of the Weak Gravity Conjecture for large-field axion inflation. We find that the Sublattice Weak Gravity Conjecture implies a constraint on the volume of the axion fundamental domain. However, we also identify conditions under which alignment and clockwork constructions, and a new variant of N -flation that we devise, can evade this constraint. We conclude that some classes of low-energy effective theories of large-field axion inflation are consistent with the strongest proposed form of the Weak Gravity Conjecture, while others are not. [ABSTRACT FROM AUTHOR]

Non-perturbatively generated effective potentials play an extremely useful and often critical role in string and inflationary model building. These potentials are typically computed by methods that assume the system is in equilibrium. For systems out of equilibrium, like an inflaton rolling down its potential, there are corrections to the semi-classical evolution due to transient phenomena. We provide a new qualitative and quantitative understanding of non-perturbative effects in real time for a wide class of toy quantum mechanical models. We derive an effective Schrödinger equation that does not rely on any notion of equilibrium and captures the low-energy dynamics supposedly described by the effective potential. We find that there are potentially large corrections to this potential that are not captured by standard equilibrium techniques, and quantify when these corrections significantly alter the effective dynamics. [ABSTRACT FROM AUTHOR]

We analyze the spectra of non-chiral and chiral bifundamental mesons arising on intersecting D7-branes in AdS × S. In the absence of magnetic flux on the curve of intersection, the spectrum is non-chiral, and the dual gauge theory is conformal in the quenched/probe approximation. For this case we calculate the dimensions of the bifundamental mesonic operators. We then consider magnetization of the D7-branes, which deforms the dual theory by an irrelevant operator and renders the mesons chiral. The magnetic flux spoils the conformality of the dual theory, and induces a D3-brane charge that becomes large in the ultraviolet, where the non-normalizable bifundamental modes are rapidly divergent. An ultraviolet completion is therefore necessary to calculate the correlation functions in the chiral case. On the other hand, the normalizable modes are very well localized in the infrared, leading to new possibilities for local model-building on intersecting D7-branes in warped geometries. [ABSTRACT FROM AUTHOR]

Female Acheta domestica did not discriminate between pairs of model calling songs (CSs) which differed only in syllable period (SP; Fig. 1). The females selected the louder CS (Fig. 2) or the CS with a faster chirp rate (CR; Fig. 3) when presented with pairs of otherwise identical CSs. A CS with an SP of 50 ms (modal for the male's CS) was preferred when it was 5 dB louder than one with a 60-ms SP while a CS with a 60-ms SP was only consistently chosen when it was 10 dB louder than a CS with a 50-ms SP (Fig. 4). A more intense CS was preferred by the females regardless of whether its CR was faster or slower than that of the CS produced at a lower intensity (Fig. 6). When CSs with SPs of 50 or 60 ms had several different CRs, the females that made a significant choice preferred a CS with a 50-ms SP regardless of whether it was produced at a faster or slower CR (Figs. 7, 8). No significant selection between CSs with 40- and 50-ms SPs resulted when they were produced at different intensities (Fig. 5) or CRs (Fig. 9). Females only significantly chose a CS with a 50-ms SP over those with 40 ms SPs when the 50-ms-SP CS was louder and produced at a different CR (Fig. 10). From these results, it was apparent that SP, intensity, and CR all influenced a female's choice of a CS, and thus the male producing it. However, our results indicate that SP was the most important feature influencing the female's choice and that intensity was more effective than CR. [ABSTRACT FROM AUTHOR]

Phonotactic selectivity of female crickets to natural and model calling songs (CSs) has been well documented. No identified acoustic interneurons or groups of them exhibited sufficiently selective responses to CSs to explain this behavioral selectivity. In this study identified acoustic interneurons were killed and pre- and post-killing phonotactic responses to model CSs were compared. [ABSTRACT FROM AUTHOR]

Sexually responsive female crickets ( Acheta domesticus) were exposed to electronically synthesized model calling songs (CSs) in an orientation arena. The female's walking during exposure to the CSs was recorded on videotape, digitized, and then analyzed using an algorithm that calculated the distance the female walked in 10 ° angle intervals (angle±5 °) with respect to the location of the sound source. The resulting polar orientation diagram (POD) presented the directional movements of 10 or more females with respect to the CS source. The PODs show that females responded to very attractive model CSs by walking directly toward the speaker. Less attractive CSs produced progressively less or no orientation toward the CS source. Each of the CS parameters was systematically changed and its attractiveness was evaluated: From these results, it is apparent that a change in any of the spectral or temporal parameters of the calling song altered its attractiveness to sexually responsive females. Thus, each feature of the calling song is encoded and used by the female cricket's nervous system in determining the attractiveness of a calling male. However, some CS features are more important than others. [ABSTRACT FROM AUTHOR]

Female Acheta domesticus can be clearly classified as sexually responsive or nonresponsive by their willingness to mount the courting male and assume the copulatory position. Females that were so classified as sexually responsive showed a definite phonotactic response to the calling song of the conspecific male. Immediate retesting of these females showed that a significant proportion exhibited very little movement in response to the sound. The females that did move in response to the calling song oriented phonotactically to the speaker also in the second trial. Females classified as nonresponsive did not react phonotactically to the calling song. The transition from the nonresponsive to the responsive state occurred within 24 h after transplanting the corpora allata from sexually responsive to nonresponsive females. [ABSTRACT FROM AUTHOR]

In young virgin Acheta domesticus females, the spiking response of the prothoracic L3 auditory interneuron discriminates between calling songs (CSs) with phonotactically attractive and unattractive syllable periods (SPs), which parallels phonotactic discrimination. Presentation of a CS with an originally attractive SP, but with the intensity modulated so as to minimize L3's selective response, results in a CS with little phonotactic attractiveness. Conversely, a CS with an originally unattractive SP becomes much more attractive when the CS is intensity modulated in ways that duplicate L3's selective response. L3's discriminatory response to CS SP deteriorates with age, in parallel with decreased phonotactic selectiveness (females, older than 14 days, typically are unselective for CS SPs). SP-selective processing, which was not apparent in these old L3s, is immediately restored by removing the contralateral ear. SP-specific information is resident in a network of neurons within the prothoracic ganglion that results in the SP selective responses of the L3 neuron in young females. Changes in the SP-selective responses of the L3 neuron are highly correlated with corresponding changes in the female's phonotactically selective behavior. [ABSTRACT FROM AUTHOR]

A platform capable of movement from one point to another under remote control has been designed for use in behavior studies. Electrical and mechanical design criterion for the platform are discussed, and schematics and engineering drawings are included. The primary application was to study communication between Glaucous-winged gulls. Other applications for the platform (as in predator-prey studies and dispersal of birds from aerodromes) are suggested. [ABSTRACT FROM AUTHOR]

The inclusion of variable costs when estimating the standard deviation of job performance in dollars has been the basis for a number of highly important advances in utility analysis (e.g. Boudreau, 1983; Boudreau & Berger, 1985). However, no studies have shown the feasibility of incorporating variable costs in situations where multiple types of costs might require global estimation of variable costs. Results obtained from a nationwide sample of insurance personnel indicated that global estimates of variable costs were feasible to obtain in such complex situations but that those costs were not a fixed percentage of the value of job performance. Judges reported that the most important inputs of information into their estimates of the value of job performance in dollars were performance and output as well as initiative of the job holder. Surprisingly, salary related information was not reported as a relatively important input. [ABSTRACT FROM AUTHOR]

This paper reports the results of studies on the neural control of the female's phonotactic response to the calling song of a male cricket, Gryllus campestris L. It deals with the processing of acoustic information contained in the temporal organization of the male's calling song by central auditory neurons. Suction electrodes were used to record the activity of auditory neurons within the intact or within splitted cervical connectives in response to the playback of a natural calling song, or to artificial chirps. Several non-habituating auditory units were repeatedly encountered as a group. These units showed clear, consistent but complex responses to the male's calling song. Individual neurons were identified that responded consistently to either the chirps as a unit (chirp coder) or to the individual pulses within a chirp (pulse coder). Auditory neurons variably responsive to the temporal features of the calling song were also observed, and the most interesting units of this group answered cyclically to the calling song with a period approximating that of the respiratory rate and perhaps that of the 'slow oscillator' suggested by Kutsch (1969) as a timer of the chirp sequences in the male. The results demonstrate that all important temporal features of the calling song in Gryllus campestris L. are coded in the activity of a few central auditory neurons which carry this information to the head ganglia. [ABSTRACT FROM AUTHOR]

Techniques for the production of a suction electrode assembly, and its attachment to a cricket ( Gryllus campestris) in such a way that the cricket can walk freely while the activity of individual interneurons in the cervical connective is clearly observable, are described. The suction electrode (tip diameter of 100 to 200 μm) is placed in contact with the surface of a connective (or peripheral nerve) and suction is applied. If the response of the unit of interest is clearly observable above background activity, the electrode assembly is attached to a supporting metal collar, which has been previously attached to the cricket. With the electrode thus supported, the cricket is released, walks freely, courts, copulates and in general behaves normally. Some examples of unit-recordings obtained from interneurons in the cervical connective of free-moving crickets are shown. [ABSTRACT FROM AUTHOR]