Boylan's Fugue in 'Sirens'

Recent discoveries in genetic studies require a revision of the fugal structure in ‘Sirens.’ We hope we can shed light on some of the remaining unsolved questions by applying these studies to an interdisciplinary approach. We will put forward our point of view on the most controversial debate on music in Joyce: does this episode of Ulysses contain the eight parts of a fuga per canonem, as the author asserted, and how can we find these parts. Our study is based on the The Sirens Copybook manuscript authenticated by Michael Groden, as well as on the further analysis by two scholars, Daniel Ferrer and Susan Brown. We believe that the role of the character Blazes Boylan in ‘Sirens’ is crucial to divide the episode in eight parts chronologically. First of all, we must point out that some of the concepts that are being used for this interdisciplinary analysis are not unambiguous and depend on the field of study alluded to. A good example is the notion of “theme,” which appears in literature as the main subject of a text, but in music it is understood as a synonym for motif, the musical material that provides a work with its own identity. Some problems of interpretation arise when this term is applied in both music and literature without a clear distinction, such as in the discussion of the eight fugal parts in ‘Sirens.’ Two authors – Stuart Gilbert and Susan Brown – claim to identify these eight sections by mentioning the “themes.” Also, the accuracy of an interdisciplinary study depends on the meticulous use of homogenous sources for the musical concepts. If not, one may argue that the scholar quotes one dictionary or another depending on his/her own interests. Susan Brown recently established that Joyce’s musical knowledge was based on the Grove’s Dictionary of Music (in this paper we will be using the abbreviation GDM). Despite detractors of Brown’s thesis, like Michelle Witen, we believe that for all practical purposes this encyclopaedia is the most useful source for establishing a standardised musical terminology. Every definition of a musical term for this research has been taken from this source

Seasonal Activity, Population Characteristics, and Age Estimation in the Aquatic Salamander, Siren intermedia nettingi (Goin)

We conducted a study of the Western Lesser Siren (Siren intermedia nettinigi), at a locality termed the Airport Road site in Jonesboro (Craighead County, AR) from November 2004 until March 2007. This site consisted of a network of roadside ditches in cultivated lawns in an industrial park. Even though sirens are known to occur frequently in ditches, most studies of the genus Siren have taken place in natural wetlands. We compiled mark-recapture data at the Airport Road site for each season to determine if the seasonal activity pattern for sirens in northeast Arkansas varied from activity data previously published from other localities in the range of this species. Capture rates were higher in the fall and spring. The predicted overall population size was 110 sirens at a density of 0.81 sirens per linear m. This density was less than the densities (in sirens/m2 ) reported by previous studies. We found two prominent peaks in sirens per size class: the first at 161-170 mm, and the second at 201-210 mm. Other researchers have assumed that the two most abundant size classes in siren populations represent one-year-old and two-year-old cohorts. The sirens captured at the Airport Road site are smaller, on average, than those reported in previous population studies. We found no significant difference between the growth rates of sirens larger than 200 mm SVL and those smaller than 200 mm snout-vent length (= SVL; P = 0.957, confidence interval -1.945, 2.045, n = 16). Our mean growth rates did not significantly differ from growth rates reported for sirens elsewhere. We sectioned siren humeri to identify and quantify lines of arrested growth (LAGs) as part of a skeletochronological analysis. The use of SVL was a poor indicator of number of LAGs. The difference in the weather pattern history in each of the voucher sirens used likely resulted in broad ranges of LAGs for each SVL size class

Tuning Gravitationally Lensed Standard Sirens

Gravitational waves emitted by chirping supermassive black hole binaries could in principle be used to obtain very accurate distance determinations. Provided they have an electromagnetic counterpart from which the redshift can be determined, these standard sirens could be used to build a high redshift Hubble diagram. Errors in the distance measurements will most likely be dominated by gravitational lensing. We show that the (de)magnification due to inhomogeneous foreground matter will increase the scatter in the measured distances by a factor ~10. We propose to use optical and IR data of the foreground galaxies to minimize the degradation from weak lensing. We find that the net effect of correcting the estimated distances for lensing is comparable to increasing the sample size by a factor of three when using the data to constrain cosmological parameters.Comment: 21 pages, 4 figures, accepted for publication in Ap

Using gravitational-wave standard sirens

Gravitational waves (GWs) from supermassive binary black hole (BBH) inspirals are potentially powerful standard sirens (the GW analog to standard candles) (Schutz 1986, 2002). Because these systems are well-modeled, the space-based GW observatory LISA will be able to measure the luminosity distance (but not the redshift) to some distant massive BBH systems with 1-10% accuracy. This accuracy is largely limited by pointing error: GW sources generally are poorly localized on the sky. Localizing the binary independently (e.g., through association with an electromagnetic counterpart) greatly reduces this positional error. An electromagnetic counterpart may also allow determination of the event's redshift. In this case, BBH coalescence would constitute an extremely precise (better than 1%) standard candle visible to high redshift. In practice, gravitational lensing degrades this precision, though the candle remains precise enough to provide useful information about the distance-redshift relation. Even if very rare, these GW standard sirens would complement, and increase confidence in, other standard candles.Comment: 10 pages, 8 figures. ApJ, in pres

Probing Gravity with Spacetime Sirens

A gravitational observatory such as LISA will detect coalescing pairs of massive black holes, accurately measure their luminosity distance and help identify a host galaxy or an electromagnetic counterpart. If dark energy is a manifestation of modified gravity on large scales, gravitational waves from cosmologically-distant spacetime sirens are direct probes of this new physics. For example, a gravitational Hubble diagram based on black hole pair luminosity distances and host galaxy redshifts could reveal a large distance extra-dimensional leakage of gravity. Various additional signatures may be expected in a gravitational signal propagated over cosmological scales.Comment: 11 pages, 1 figure, accepted for publication in ApJ Letter

Modified gravitational-wave propagation and standard sirens

Studies of dark energy at advanced gravitational-wave (GW) interferometers normally focus on the dark energy equation of state $w_{\rm DE}(z)$. However, modified gravity theories that predict a non-trivial dark energy equation of state generically also predict deviations from general relativity in the propagation of GWs across cosmological distances, even in theories where the speed of gravity is equal to $c$. We find that, in generic modified gravity models, the effect of modified GW propagation dominates over that of $w_{\rm DE}(z)$, making modified GW propagation a crucial observable for dark energy studies with standard sirens. We present a convenient parametrization of the effect in terms of two parameters $(\Xi_0,n)$, analogue to the $(w_0,w_a)$ parametrization of the dark energy equation of state, and we give a limit from the LIGO/Virgo measurement of $H_0$ with the neutron star binary GW170817. We then perform a Markov Chain Monte Carlo analysis to estimate the sensitivity of the Einstein Telescope (ET) to the cosmological parameters, including $(\Xi_0,n)$, both using only standard sirens, and combining them with other cosmological datasets. In particular, the Hubble parameter can be measured with an accuracy better than $1\%$ already using only standard sirens while, when combining ET with current CMB+BAO+SNe data, $\Xi_0$ can be measured to $0.8\%$ . We discuss the predictions for modified GW propagation of a specific nonlocal modification of gravity, recently developed by our group, and we show that they are within the reach of ET. Modified GW propagation also affects the GW transfer function, and therefore the tensor contribution to the ISW effect.Comment: 25 pages, 23 figures: v3: several significant improvement