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This study aims to determine the effect of regulating the provision of nitrogen fertilizer on several rice varieties on the growth and yield of rice in ratoon system at the Tidal swampland. A split plot design was employed in this experiment. The main plot was nitrogen fertilizer application (N) consisting of N1, N2, N3, and N4. The subplot is rice varieties (V) consisting of Inpari 30 (V1), Inpara 3 (V2), Inpari 33 (V3), Inpari 43 (V4) and Hipa 5 Ceva (V5). The results showed that ½ dose nitrogen fertilization given at planting + ½ dose at primordia had a good effect on the growth and yield of the main crop, whereas 1/3 dose nitrogen fertilization given at planting + 1/3 dose at primordia + 1/3 dose at harvest tends to have a good effect on ratoon yield. Variety Hipa 5 Ceva produced highest yield of unhusked rice (i.e. 4.9 tons ha-1 for the main crop and 2.71 tons ha-1 for ratoon) at (N3): 135 kg N ha-1 fertilizer, when ½ dose was given at planting + ½ dose at primordia. The variety Hipa 5 Ceva with various nitrogen fertilization strategies provided the highest total grain yield in the ratoon system at tidal swampland.

[GROWTH AND YIELD OF EIGHT SWEET CORN GENOTIPE ORGANICALLY GROWN IN SWAMPLAND]. Sweet corn (Zea mays saccharata Sturt) has a greater advantage than feed corn because of its early maturity and the price is more expensive. Recently, the need for sweet corn is higher than its production. To overcome these problems, it is necessary to expand the planting area by utilizing sub-optimal land such as swamps of low fertility. Agricultural intensification can be carried out through the use of organic materials to meet nutrient needs for growth and yield of sweet corn. Determination of varieties suitable for planting in sub-optimal land is also an effort to increase the productivity of sweet corn in swampland. This study aims to determine the potential of sweet corn genotype for organically cultivated in swampland. The material used in this study consisted of seven sweet corn genotypes and one comparative variety planted in experimental plots based on a Randomized Completely Block Design (RCBD) with three replications. The variables evaluated in this study were the growth, development, yield, and yield components of sweet corn. The results showed that the 8 sweet corn genotypes tested had significantly different in plant height, number of leaves, number of rows of seeds per cob, and yields per plot. Caps 17 B x Caps 22 and Caps 3 x Caps 5 are genotypes that have better growth than the comparative variety. On the other hand, the yield and yield components of the comparative variety was higher among the other genotypes tested.

The Cibitung - Cilincing toll road is faced with problems across many rivers and marshlands where the swampland is identified as clay. In building construction, the foundation is very important in bearing the burden of working on the upper construction. This Final Project contains the calculation of the carrying skin capacity and the end resistance of the pile using the Suyono method. S and Nakazawa (1990) based on N-SPT data and dynamic methods using the formula of Hiley (1930) based on the pile driving record data, then proceed to the calculation of the carrying capacity of the pile group, after that calculating the decrease of the pile using the Vesic method (1977). From the results of the analysis conducted by the author in calculating the bearing capacity to using N-SPT data and pile driving record data, the author gets that from the pile diameter of 50 cm, the carrying capacity of a single-pole is 66-ton, obtained using the method of Suyono S and Nakazawa, based on the formula of Hiley, it is obtained 139.34 tons, and settlement that occurred in the pile group foundation was an immediate settlement is 11.2 cm and a consolidation settlement is 6.2 cm.

We argue that under certain assumptions the quantum break time approach and the trans-Planckian censorship conjecture both lead to de Sitter swampland constraints of the same functional form. It is a well known fact that the quantum energy-momentum tensor in the Bunch-Davies vacuum computed in the static patch of dS breaks some of the isometries. Proposing that this is a manifestation of quantum breaking of dS, we analyze some of its consequences. In particular, this leads to a thermal matter component that can be generalized to string theory in an obvious way. Imposing a censorship of quantum breaking, we recover the no eternal inflation bound in the low temperature regime, while the stronger bound from the dS swampland conjecture follows under a few reasonable assumptions about the still mysterious, presumably topological, high-temperature regime of string theory., 60 pages, 12 figures, v2: major revision of section 2, final version to appear in JHEP

In this essay we will take a wonderful ride on a dark bubble with strings attached, which carries our universe out of the swampland and makes it realizable in the landscape of string theory. To find the way to the landscape, we make use of apparently hostile corners of the swampland and their instabilities., Comment: This essay received an Honorable Mention in the 2021 Essay Competition of the Gravity Research Foundation

Swampland Conjectures have attracted quite some interest in the Cosmological Community. They have been shown to have wide ranging implications , like Constraints on Inflationary Models, Primordial Black Holes etc. to name a few. A particularly revealing insight on dark energy also shows that one can have the dark energy equation of state for a quintessence scenario to be signficantly different than -1 after one takes into account the refined dS conjecture. Another interesting issue with the swampland conjectures is that they have been shown to be incompatible with single field inflationary models in GR based cosmology. In our previous work we have, however, showed that single field inflationary models are quite compatible with swampland conjectures in their usual string theoretic form in a large class of modified cosmological scenarios. Building on that work, we now show that in modified cosmological scenarios where the early universe expansion was driven by single field inflation , one can have the dark energy equation of state to be significantly different from -1 even if we just take into account the original dS conjecture, let alone the refined form of that. We thereby show that one does not need to apply a step function approach towards inflation in order to have an observable distinction between constant and non constant dark energy models in the context of the swampland conjectures., Comment: v2, 9 pages long with added references and minor details

We extend the swampland from effective field theories (EFTs) inconsistent with quantum gravity to EFTs inconsistent with quantum supergravity. This enlarges the swampland to include EFTs that become inconsistent when the gravitino is quantized. We propose the ``gravitino swampland conjecture'': the gravitino sound speed must be nonvanishing in all EFTs that are low-energy limits of quantum supergravity. This seemingly simple statement has important consequences for both theories and observations. The conjecture is consistent with and supported by the Kachru-Kallosh-Linde-Trivedi and large volume scenarios for moduli stabilization in string theory.

We argue that, in the presence of time-dependent fluxes and quantum corrections, four-dimensional de Sitter solutions should appear in the type IIB string landscape and not in the swampland. Our construction considers generic choices of local and non-local quantum terms and satisfies the no-go and the swampland criteria, the latter being recently upgraded using the trans-Planckian cosmic censorship. Interestingly, both time-independent Newton constant and moduli stabilization may be achieved in such backgrounds even in the presence of time-dependent fluxes and internal spaces. However, once the time-dependence is switched off, any four-dimensional solution with de Sitter isometries appears to have no simple effective field theory descriptions and is back in the swampland., 30 pages, 4 figures; v2: Typos corrected and references added; v3: Typos corrected and more references added

Geographically, Hulu Sungai Utara Regency is one of the regencies in South Kalimantan which is one of the regions producing brown rice with good results to develop. The land in Hulu Sungai Utara Regency is an average of swampland and rainfed, to plant brown rice only once a year. Brown rice is one type of rice that contains high nutrition. Based on the nutritional content, brown rice is very good for food-insecure areas, especially people who are malnourished. Farmers are less interested in planting brown rice although the selling price of red rice is higher than white rice and there is public awareness of the importance of the nutritional content of red rice for health so that the prospect of brown rice is very good to be cultivated. This research is raining to find out the costs, revenues, and profits of brown rice, to find out compensation for brown rice farming and to find out the problems faced in brown rice farming. The type of data used includes primary data and secondary data. The total sample of respondents was 11 farmers using the census method. The average land area used by brown rice farmers is 0.46 Ha. Based on the results of research on brown rice, it includes preparation of seedlings, land preparation, planting, maintenance, harvesting. The total costs incurred by farmers are Rp. 7,940,572, - per farm or Rp.17,303,649, - per ha. The total farmer income is IDR 14,784,000 per farm or IDR 32,139,130 ​​per ha. The total income of brown rice farmers is IDR 13,730,053 per farm or IDR 29,847,942 per ha. The benefits obtained by farmers are Rp.6,843,428, - per farm or Rp.14,835,481, - per ha. Repayment of farmers' capital is Rp.6,843,428, - per farm. Land compensation is Rp.6,843,428, - per farm. Retribution for labor in the family of brown rice farmers is IDR 6,799,348 per farm. The problem of brown rice farmers is that it is mostly an obstacle in regulating water, the difficulty of obtaining new land to cultivate brown rice, the difficulty of marketing the results of red rice to the community and the benefits of labor received by the red rice farmers smaller than the UMR of Hulu Sungai Regency North.

A successful rice production on swampland would require a planting material from high yielding varieties adaptated to the swampy ecosystem. This study was carried out to compare the growth and yield characteristics of five rice lines and a check variety as grown on non-tidal swampland. The lines were F4 generation of bulk selection from the crosses involving Bengkulu swamp rice landraces (Hanafi Putih, Tigo-tigo, Harum Curup, and Lubuk Durian) and high yielding varieties for the irrigated field (Sidenuk and Bestari). The trial was conducted on a shallow non-tidal swampland with stagnant inundation no more than 50 cm in depth often occurred during the plant life cycle. The lines and the check variety (Inpara 4) were arranged in a randomized complete block design with three replications. Observations were made for the agronomic performances of the plant, including plant height, total tiller number clump-1, effective tiller number clump-1, heading date, maturity date, panicle length, grain number panicle-1, 100-grain weight, and grain yield clump-1. Significant variation among the genotypes was found for all observed traits. On average, the evaluated lines showed comparable growth and yield performances to the check variety. Tigo-tigo × Bestari was the tallest line and potential for medium depth swampland. This line showed good overall agronomic performances and yielded relatively higher than the check variety, but delayed in attaining maturity. For shallow swampland, Hanafi Putih x Sidenuk exhibited the most potent line by having good overall agronomic and yield performances, except late in maturity. For early maturing line, Lubuk Durian x Hanafi Putih showed its potential for shallow swampland. Although this line was not the best, it showed better overall agronomic performances than the check variety. Keywords: F4 lines, growth and yield performance, rice landrace, swampland, plant maturity

Realising de Sitter vacua in string theory is challenging. For this reason it has been conjectured that de Sitter vacua inhabit the Swampland of inconsistent low-energy effective theories coupled to gravity. Since de Sitter is an attractor for $\Lambda$CDM, the conjecture calls $\Lambda$CDM into question. Reality appears sympathetic to this idea as local measurements of the Hubble constant $H_0$ are also at odds with $\Lambda$CDM analysis of Planck data. This tension suggests that the de Sitter state is unstable, thereby implying a turning point in the Hubble parameter. We present a model relieving this tension, which predicts a turning at small positive redshift $z_*$ that is dictated by present-day matter density $\omega_m$. This feature is easily identified by homogeneous surveys covering redshifts $z \leq 0.1$. We comment on the implications for the Swampland program., Comment: v1 4 pages, comments welcome; v2 replacing mistakenly uploaded unfinished version; v3 arguments revised; v4; v5 matches published version, further changes outcome of the review process

Floodwaters from the Assiniboine River are typically diverted to Lake Manitoba and then Lake St. Martin to save the City of Winnipeg and Portage la Prairie from flooding. The four Indigenous communities living Lake St. Martin basin experienced many negative impacts, including long-term displacement after the 2011 flood. Data analysis of historical water levels of Lake Manitoba and Lake St. Martin were conducted to understand the impact of control structures and water levels. Satellite imagery allowed geographic information system (GIS) raster analysis of the shoreline change of Lake St. Martin before and after the 2011 super flood. From 1986 to 2010, the Lake St. Martin area increased slightly by approximately 0.63% but in 2011 the lake area increased by 13%. 11,000 acres were lost mainly around Lake St. Martin First Nation (LSMFN) reserve and the Little Saskatchewan First Nation, as a result and many houses and other buildings (churches, band offices, etc.) flooded in these communities. The shoreline change analysis showed that, in particular, the west and north shoreline of Lake St. Martin lost its beaches and lakefront properties, to become swampland after the 2011 flood. Thousands of Indigenous people were displaced for eight years, as the community could only start to rebuild its infrastructure and houses on higher ground after a government settlement was reached.

P ymatuning Swamp lies buried beneath Pymatuning Reservoir, subdued but not forgotten, its legacy still visible in the hydric soils and wetlands of the reservoir backwaters (figure 1). This is a story of a changing climate, melting glaciers, ancient lakes filled with sediments, swamplands of northwestern Pennsylvania, and humanity's unceasing efforts to mold and manage the natural landscape for human uses. The footprint of the Adena culture, hunters and gatherers who grew corn ( Zea mays L.), beans, and squash 3,000 to 1,000 years ago near the wetlands, was light. Their settlements thrived for a short period along Pymatuning Creek, the Shenango River, and Conneaut Lake swamp. By the late 1700s, Europeans attempted to settle the wet, forested region incentivized by the Pennsylvania Land Act. The human solution to this wetland wilderness of abundant white pine ( Pinus strobus ), beaver ( Castor canadensis ), and wildlife that was nearly impenetrable to travel was to construct the Beaver to Erie Canal in the 1830s. This extension of the Erie Canal connected the Ohio River via Beaver River north to Shenango River, over the continental divide to Lake Erie and quickened the transport and exchange of the wilderness's raw materials and East Coast's dry goods. The Pymatuning…

A Correction to this paper has been published: https://doi.org/10.1140/epjc/s10052-021-09130-8

Rice is still a strategic commodity in Indonesia. The need for rice to fulfill staple food every year tends to increase in line with the rate of population growth in Indonesia Lampung Province government continues to strive for various programs to fulfill food. One of the efforts made is optimizing the use of marginal land in the swampland. The swampland area in Lampung is about 162,930 ha, consisting of 68,900 ha of tidal swampland and 94,030 ha of lowland swamps. Lampung potential swampland, has the opportunity to meet food needs, especially rice. Problems of swampland rice farming which commonly found are environmental stress related to water and land management, unadaptive rice commodities and applying appropriate cultivation technology. Swampland rice farming is expected to provide added value and benefits for farmers. This study aims to analyze rice farming in the tidal swampland of Tulang Bawang Regency, Lampung Province. The farm study was carried out by planting rice on a 1 ha tidal swampland. The rice planted is the existing local rice varieties. The study was carried out in the second planting season. The results of the study showed that the growth and production of rice is quite good. Rice farming in the tidal wetland provides an advantage over an R/C ratio of 1.46 and an R/C ratio of 1.72. So that rice farming in the tidal swampland is feasible.

Constraints on a dark energy dominated Universe are obtained from an interplay between Bayesian Machine Learning and string Swampland criteria. The approach here differs from previous studies, since in the generative process Swampland criteria are used and, only later, the results of the fit are validated, by using observational data-sets. A generative process based Bayesian Learning approach is applied to two models and the results are validated by means of available $H(z)$ data. For the first model, a parametrization of the Hubble constant is considered and, for the second, a parametrization of the deceleration parameter. This study is motivated by a recent work, where constraints on string Swampland criteria have been obtained from a Gaussian Process and $H(z)$ data. However, the results obtained here are fully independent of the observational data and allow to estimate how the high-redshift behavior of the Universe will affect the low-redshift one. Moreover, both parameterizations in the generative process, for the Hubble and for the deceleration parameters, are independent of the dark energy model. The outcome, both data- and dark energy model-independent, may highlight, in the future, the borders of the Swampland for the low-redshift Universe and help to develop new string-theory motivated dark-energy models. The string Swampland criteria considered might be in tension with recent observations indicating that phantom dark energy cannot be in the Swampland. Finally, a spontaneous sign switch in the dark energy equation of state parameter is observed when the field traverses are in the $z\in[0,5]$ redshift range, a remarkable phenomenon requiring further analysis., Comment: 12 pages, 4 figures, 2 tables

In this paper, we study a constant-roll inflationary model in the presence of a noncommutative parameter with a homogeneous scalar field minimally coupled to gravity. The specific noncommutative inflation conditions proposed new consequences. On the other hand, we use anisotropic conditions and find new anisotropic constant-roll solutions with respect to noncommutative parameter. Also, we will plot some figures with respect to the specific values of the corresponding parameter and the swampland criteria which is raised from the exact potential obtained from the constant-roll condition. Finally, different figures lead us to analyze the corresponding results and also show the effect of above mentioned parameter on the inflationary model., 18 pages, 16 figures. accepted by The European Physical Journal C

In this work, we shall study a class of [Formula: see text] gravity models which during the inflationary era, which is the large curvature regime, result to an effective inflationary Lagrangian that contains a rescaled Einstein–Hilbert term [Formula: see text] in the presence of a canonical minimally coupled scalar field. The dimensionless parameter [Formula: see text] is chosen to take values in the range [Formula: see text] and the main motivation for studying these rescaled Einstein–Hilbert [Formula: see text] gravities, is the fact that the rescaled action may render an otherwise incompatible canonical scalar field theory with the Swampland criteria, to be compatible with the Swampland criteria and specifically the distance conjecture and the de Sitter conjecture, without considering the refined de Sitter conjecture however. As we will show, by studying a large number of inflationary potentials appearing in the 2018 Planck collaboration paper for the constraints on inflation, the simultaneous compatibility with both the Planck constraints and the aforementioned two Swampland criteria is achieved for some models, and the main characteristic of the models for which this is possible is the small value that the parameter [Formula: see text] must take.

The swampland is the set of seemingly consistent low-energy effective field theories that cannot be consistently coupled to quantum gravity. In this review we cover some of the conjectural properties that effective theories should possess in order not to fall in the swampland, and we give an overview of their main applications to particle physics. The latter include predictions on neutrino masses, bounds on the cosmological constant, the electroweak and QCD scales, the photon mass, the Higgs potential and some insights about supersymmetry., 36 pages. Contribution to the Open Access Special Issue "Women Physicists in Astrophysics, Cosmology and Particle Physics'', Universe, ISSN 2218-1997, IF 1.752. v2: minor changes, references added

In this review we argue that four-dimensional effective field theory descriptions with de Sitter isometries are allowed in the presence of time-dependent internal degrees of freedom in type IIB string landscape. Both moduli stabilizations and time-independent Newton constants are possible in such backgrounds. However once the time-dependences are switched off, there appear no possibilities of effective field theory descriptions and these backgrounds are in the swampland.

The reconstruction of a k-essence inflationary universe, considering the unification between the swampland criteria and the attractor given by the scalar spectral index $n_S(N)$ together with the slow roll parameter $\epsilon(N)$in terms of the number of $e$-folds $N$ is studied. In the context of a coupling of the form $L(\phi)\,X$ in the k-essence model, we find the effective potential $V$ and the coupling parameter $L$ in terms of the scalar spectral index and the slow roll parameter under a general formalism. To apply the unification in our model, we consider some examples in order to rebuild the effective potential $V(\phi)$ and the coupling parameter $L(\phi)$ as a function of the inflaton field $\phi$. Here, we find that the reconstruction gives rise to an exponential potential and also to natural and hyperbolic inflation, respectively. Thus, in this article we show that it is possible to unify the theoretical foundations from the swampland criteria and the observational parameters corroborated by observations, in the reconstruction of an inflationary universe.

We study de Sitter configurations in ten-dimensional string models where supersymmetry is either absent or broken at the string scale. To this end, we derive expressions for the cosmological constant in general warped flux compactifications with localized sources, which yield no-go theorems that extend previous works on supersymmetric cases. We frame our results within a dimensional reduction and connect them to a number of Swampland conjectures, corroborating them further in the absence of supersymmetry. Furthermore, we construct a top-down string embedding of de Sitter brane-world cosmologies within unstable anti-de Sitter landscapes, providing a concrete realization of a recently revisited proposal., 32 pages + appendices, 12 figures; v2: typos corrected, references added

In the recent time, inflationary cosmology is facing an existential crisis due to the proposed Swampland criterion which aims to evade any (meta-)stable de Sitter construction within the String landscape. It is been realised that a single field slow roll inflation is inconsistent with the Swampland criterion unless the inflationary model in realised in some non standard scenario such as Warm inflation or the Braneworld scenario. In \cite{Dimopoulos}, Dimopoulos and Owen introduced a new class of model of inflation dubbed as the power law plateau inflation in the standard cold inflationary scenario. But to realise this model in the standard scenario consistent with observation, they had to introduce a phase of thermal inflation. In this paper we have analysed this model in the braneworld scenario to show that for some choice of the parameters defining the model class, one can have an observationally consistent power law plateau without any phase of thermal inflation. We have also shown that, for the correct choice of model parameters, one can easily satisfy the Swampland criterion. Besides, for a particular choice of the potential one can also satisfy the recently proposed Trans-Planckian Censorship Conjecture., Comment: 14 pages,Matches published version, Section on TCC added

In this paper, we propose a new Swampland condition, the Trans-Planckian Censorship Conjecture (TCC), based on the idea that in a consistent quantum theory of gravity sub-Planckian quantum fluctuations should remain quantum and never become larger than the Hubble horizon and freeze in an expanding universe. TCC leads to conditions that are similar to the refined dS Swampland conjecture. For example, applied to the case of cosmologies driven only by a scalar field, the TCC imposes an upper bound of $2/\sqrt{d-2}$ on the asymptotic value of $|V'|/V$. Additionally, it implies that a monotonically changing potential across a field space interval $\Delta\phi$ must satisfy $V\leq V_{\max}~\exp(-2\Delta\phi/\sqrt{(d-1)(d-2)})$. Like the dS Swampland conjecture, the TCC forbids long-lived meta-stable dS spaces, but allows sufficiently short-lived ones., Comment: The abstract has been modified and a short note has been added at the end of the introduction to explain the update

Cosmological inflation is not the only early universe scenario consistent with current observational data. I will discuss the criteria for a successful early universe cosmology, compare a couple of the proposed scenarios (inflation, bouncing cosmologies, and the emergent scenario), focusing on how future observational data will be able to distinguish between them. I will argue that we need to go beyond effective field theory in order to understand the early universe, and that principles of superstring theory will yield a non-singular cosmology.

We consider supergravity theories with 16 supercharges in Minkowski space with dimensions d>3. We argue that there is an upper bound on the number of massless modes in such theories depending on d. In particular, we show that the rank of the gauge symmetry group G in d dimensions is bounded by rG≤26−d. This in particular demonstrates that four-dimensional N=4 SYM theories with rank bigger than 22, despite being consistent and indeed finite before coupling to gravity, cannot be consistently coupled to N=4 supergravity in Minkowski space and belong to the swampland. Our argument is based on the swampland conditions of completeness of spectrum of defects as well as a strong form of the distance conjecture and relies on unitarity as well as supersymmetry of the world sheet theory of BPS strings. The results are compatible with known string constructions and provide further evidence for the string lamppost principle: that string theory lamppost seems to capture all consistent quantum gravitational theories.

Perhaps the greatest challenge for fundamental theories based on compactification from extra dimensions is accommodating a period of accelerated cosmological expansion. Previous studies have identified constraints imposed by the existence of dark energy for two overlapping classes of compactified theories: (1) those in which the higher dimensional picture satisfies certain metric properties selected to reproduce known low energy phenomenology; or (2) those derived from string theory assuming they satisfy the Swampland conjectures. For either class, the analyses showed that dark energy is only possible if it takes the form of quintessence. In this paper, we explore the consequences for theories that belong to both classes and show that the joint constraints are highly restrictive, leaving few options., Comment: 12 pages, 3 figures

In the context of string theory, several conjectural conditions have been proposed for low energy effective field theories not to be in swampland, the UV-incomplete class. The recent ones represented by the de Sitter and trans-Planckian censorship conjectures in particular seem to conflict with the inflation paradigm of the early universe. We first point out that scenarios where inflation is repeated several times (multiphase inflation) can be easily compatible with these conjectures. In other words, we relax the constraint on the single inflation for the large scale perturbations to only continue at least around 10 e-folds. In this context, we then investigate if a spectator field can be a source of the almost scale-invariant primordial perturbations on the large scale. As a consequence of such an isocurvature contribution, the resultant perturbations exhibit the nonvanishing non-Gaussianity in general. Also the perturbation amplitude on smaller scales can be completely different from that on the large scale due to the multiplicity of inflationary phases. These signatures will be a smoking gun of this scenario by the future observations.

During an accelerated expansion of the Universe, quantum fluctuations of sub-Planckian size can be stretched outside the horizon and be regarded effectively classical. Recently, it has been conjectured that such horizon-crossing of trans-Planckian modes never happens inside theories of quantum gravity (the trans-Planckian censorship conjecture, TCC). We point out several conceptual problems of this conjecture, which is in itself formulated as a statement on the restriction of possible scenarios in a theory: by contrast a standard swampland conjecture is a restriction of possible theories in the landscape of the quantum gravity. We emphasize the concept of swampland universality, i.e. that a swampland conjecture constrains any possible scenario in a given effective field theory. In order to illustrate the problems clearly we introduce several versions of the conjecture, where TCC condition is imposed differently to scenarios realizable in a given theory. We point out that these different versions of the conjecture lead to observable differences: a TCC violation in another Universe can exclude a theory, and such reduction of the landscape restricts possible predictions in our Universe. Our analysis raises the question of whether or not the trans-Planckian censorship conjecture can be regarded as a swampland conjecture concerning the existence of UV completion., Comment: 12 pages, 7 figures

In String Gas Cosmology, the simplest shape modulus fields are naturally stabilized by taking into account the presence of string winding and momentum modes. We determine the resulting effective potential for these fields and show that it obeys the de Sitter conjecture, one of the swampland criteria for effective field theories to be consistent with superstring theory., Comment: 4 pages

We study moduli stabilization for type IIB orientifold compactifications on Calabi-Yau three-folds with (non-)geometric fluxes. For this setting it is possible to stabilize all closed-string moduli classically without the need for non-perturbative contributions, and examples of stable de-Sitter constructions can be found in the literature which violate a prominent swampland conjecture. In this paper we derive general properties of non-geometric flux-compactifications, we argue that the contribution of fluxes to the tadpole cancellation conditions should be similar to D-branes (and not anti-D-branes), and we exclude supersymmetric Minkowski vacua for certain cases. We also reassess known stable de-Sitter constructions with (non-)geometric H-, F-, Q- and R-fluxes and argue that these are not consistent in string theory., Comment: 37 pages; v2: references added, discussion in section 3 extended, published version

The scenario of two components warm tachyon inflation is considered where the tachyon field plays the role of inflaton and drives inflation. During inflation, the tachyon scalar field interacts with the other component of the Universe which is considered as photon gas, i.e. radiation. The interacting term contains a dissipation coefficient, and the study is modeled based on two different and familiar choices of the coefficient that have been {studied} in the literature. By applying the latest observational data, the acceptable ranges for the free parameters of the model are obtained. For any choice inside the {estimated} ranges, there is an acceptable concordance between the theoretical predictions and observations. Whereas the model is established based on some assumptions, it is vital to check their validity for the obtained values of the free parameters of the model. It is realized that the model is not self-consistent for all values of the ranges and sometimes the assumptions are violated. Therefore, {to have both self-consistency and agreement with data} the parameters of the model need to be {constrained} again. After that, we are going to consider the recently proposed swampland conjecture, which imposes two conditions on the inflationary models. These criteria could rule out some of the inflationary models, however, warm inflation is known as one of those models that could successfully satisfy the swampland criteria. A precise investigation determines that the proposed warm tachyon inflation could not satisfy the swampland criteria for some cases. In fact, for the first case of the dissipation coefficient, where there is dependency only on the scalar field, the model could agree with observational data ..., Comment: 14 pages, 11 figures, Submitted to Chinese Physics C

We revisit the Einstein-Gauss-Bonnet theory in view of the GW170817 event, which compels that the gravitational wave speed is equal to in natural units. We use an alternative approach compared to one previous work of ours, which enables us to express all the slow-roll indices and the observational indices as functions of the scalar field. Using our formalism we investigate if the Swampland criteria are satisfied for the Einstein-Gauss-Bonnet theory and as we demonstrate, the Swampland criteria are satisfied for quite general forms of the potential and the Gauss-Bonnet coupling function ξ(φ), if the slow-roll conditions are assumed to hold true., This work is supported by MINECO (Spain), FIS2016-76363-P, and by project 2017 SGR247 (AGAUR, Catalonia) (S.D.O).

We argue that dark energy with multiple fields is theoretically well-motivated and predicts distinct observational signatures, in particular when cosmic acceleration takes place along a trajectory that is highly non-geodesic in field space. Such models provide novel physics compared to $\Lambda$CDM and quintessence by allowing cosmic acceleration on steep potentials. From the theoretical point of view, these theories can easily satisfy the conjectured swampland constraints and may in certain cases be technically natural, potential problems which are endemic to standard single-field dark energy. Observationally, we argue that while such multi-field models are likely to be largely indistinguishable from the concordance cosmology at the background level, dark energy perturbations can cluster, leading to an enhanced growth of large-scale structure that may be testable as early as the next generation of cosmological surveys., Comment: 9 pages, 1 figure. Extended discussion, added references, matches published version

There have been many attempts to construct de Sitter space-times in string theory. While arguably there have been some successes, this has proven challenging, leading to the de Sitter swampland conjecture: quantum theories of gravity do not admit stable or metastable de Sitter space. Here we explain that, within controlled approximations, one lacks the tools to construct de Sitter space in string theory. Such approximations would require the existence of a set of (arbitrarily) small parameters, subject to severe constraints. But beyond this one also needs an understanding of big-bang and big-crunch singularities that is not currently accessible to standard approximations in string theory. The existence or non-existence of metastable de Sitter space in string theory remains a matter of conjecture., Comment: 20 pages. v2: references added; v3, v4: typos fixed

A number of Swampland conjectures and in particular the Trans-Planckian Censorship Conjecture (TCC) suggest that de Sitter space is highly unstable if it exists at all. In this paper we construct effective theories of scalars rolling on potentials which are dual to a chain of short-lived dS spaces decaying from one to the next through a cascade of non-perturbative nucleation of bubbles. We find constraints on the effective potential resulting from various swampland criteria, including TCC, Weak Gravity Conjecture and Distance Conjecture. Surprisingly we find that TCC essentially incorporates all the other ones, and leads to a subclass of possible dual effective potentials. These results marginally rule out emergence of eternal inflation in the dual effective theory. We discuss some cosmological implications of our observations., Comment: 21 pages + appendices, 7 figures. v2: References added v3: References corrected

The effective vacuum energy density contributed by the non-trivial contortion distribution and the bare vacuum energy density can be viewed as the energy density of the auxiliary quintessence field potential. We find that the negative bare vacuum energy density from string landscape leads to a monotonically decreasing quintessence potential while the positive one from swampland leads to the metastable or stable de Sitter-like potential. Moreover, the non-trivial Brans-Dicke like coupling between the quintessence field and gravitation field is necessary in the latter case.

Since the beginning of the 20th century, tideland reclamation as a huge project has continuously extended from inland to the sea for the socioeconomic development, like Zhejiang, Jiangsu and other coastal regions in China. The increase of land area alleviated the contradiction of supply and demand between human and land, which provided the guarantee for agricultural production and industrial development. However, marine ecological environment has been seriously damaged due to the increasing scale of tideland reclamation. This paper took the Hangzhou Bay in the Yangtze River Delta as a study area to explore the evolution law, socioeconomic effect and eco-environmental effect of reclaimed land from 1985 to 2015. The result showed that as follows: (1) The area of tideland reclamation was 460.67 km2 with 16.57% cultivated land and 15.93% construction land, and its land use was inefficient; (2) Land use change has spatial and temporal difference, the speed of tideland reclamation had been increasing from 1985 to 2015 in time and the scale of reclaimed land in the southern (84.07%) of Hangzhou Bay was larger than the northern region (15.93%) in space; (3) The evolution law of land use was from tideland to swampland and coastal waters to agricultural facility land, to cultivated land to industrial-mining land to idle land, rural-urban construction land, and formed obviously hierarchical structure; (4) Effect analysis of land use change found that the socio-economic effect had increased but the eco-environmental effect had decreased from 1985 to 2015, it reflected socioeconomic effect was acquired through sacrificing ecoenvironmental effect; (5) It pointed out the existing problems on land extensive inefficient, environmental degradation and economy excessive growth without scientific planning, and offered some suggestions in land comprehensive improvement project, industrial transformation and upgrading and scientific planning and legal safeguard to promote sustainable development in the Hangzhou Bay in the new period.

We present a proposal to relate the de Sitter Conjecture (dSC) to the Covariant Entropy Bound (CEB). By assuming an early phase of accelerated expansion where the CEB is satisfied, we take into account a contribution from extra-dimensions to the four-dimensional entropy which restricts the values of the usual slow-roll parameters. We show in this context that the dSC inequalities follow from the CEB -- including their mutual exclusion -- in both single and multi-field inflationary scenarios. We also observe that the order one constants, c and c' in the conjecture are given in terms of physical quantities such as the change in entropy over time, the Hubble constant and the dynamics of the effective scalar fields. Finally, we give a simple example to illustrate a possible contribution to the four-dimensional entropy from a flux string scenario., 28 pages, 3 figures. Typos corrected

We investigate the consequences of combining swampland conjectures with the requirement of asymptotic safety. To this end, we explore the infrared regime of asymptotically safe gravity in the quadratic one-loop approximation, and we identify the hypersurface spanned by the endpoints of asymptotically safe renormalization group trajectories. These comprise the allowed values of higher-derivative couplings as well as standard logarithmic form factors. We determine the intersection of this hypersurface with the regions of parameter space allowed by the weak-gravity conjecture, the swampland de Sitter conjecture, and the trans-Planckian censorship conjecture. The latter two depend on some order-one constants, for generic values of which we show that the overlap region is a proper subspace of the asymptotically safe hypersurface. Moreover, the latter lies inside the region allowed by the weak gravity conjecture assuming electromagnetic duality. Our results suggest a non-trivial interplay between the consistency conditions stemming from ultraviolet completeness of the RG flow, black hole physics, and cosmology., Comment: 33 pages, 8 figures. Invited contribution to the special issue "Asymptotic Safety in Quantum Gravity" in Universe. V2: figures added, typos fixed. Matches published version

The efforts to increase rice production in swampland are faced with various obstacles, including extreme climate change (drought and flooding). To overcome the drought and flooding conditions is by planting suitable rice varieties for its conditions. During el nino, very early maturity varieties could be planted such as Inpari 12, 13, 18, 19, and 20 (99 to 104 days old). Somewhat drought tolerant varieties, such as Inpari 38, 39, and 40. In la nina conditions could be planted Inpara 3, 4, and 5 because these varieties were moderately submergence tolerant. Inpara 3 was tolerant to submergence for 6 days, while Inpara 4 and 5 were tolerant for 14 days in the vegetative phase. Furthermore, the Inpari 29 and 30 Ciherang Sub-1 could also submergence tolerant for 14 and 15 days, respectively. By planting early maturity and submergence tolerant varieties, it is hoped that rice production in swampland can be maintained under climate change. This paper is a review and the purpose of this paper is to anticipate the effects of extreme climate change (el-nino and la-nina) through using rice varieties in swamplands and strategy for selecting the varieties so that they can produce under extreme climate changes.

The purpose of this study was to estimate the production and profit function by farmers and to analyze the relative economic efficiency of rice farming in two typologies of wetland, tidal swampland and freshwater swampland. The analysis showed that the production facilities in the study area were very influential on the rice farming profit, so an increase in the high price of production facility would lead to a decrease in profit, which in turn would lower the level of farmers’ welfare. Under optimal conditions where maximum profit was reached, the effects of variable input prices and the input number remained significant except for the value of the equipment used. Based on the value of the coefficient function of fertilizer demand, pesticide and labor were inelastic towards the price while the seed input was elastic. Rice farming in the study area had decreasing returns to scale. It indicated that the increase in inputs was higher than the increase in returns. Keywords: profit function, rice farming, returns to scale

Some histories of California describe nineteenth-century efforts to reclaim the extensive swamplands and shallow lakes in the southern part of California's San Joaquin Valley – then the largest natural wetlands habitat west of the Mississippi River – as a herculean venture to tame a boggy wilderness and turn the region into an agricultural paradise. Yet an 1850s proposition for draining those marshes and lakes primarily was a scheme to improve the state's transportation. Swampland reclamation was a secondary goal. Transport around the time of statehood in 1850 was severely lacking in California. Only a handful of steamboats plied a few of the state's larger rivers, and compared to the eastern United States, roads and railroads were nearly non-existent. Few of these modes of transportation reached into the isolated San Joaquin Valley. As a result, in 1857 the California legislature granted an exclusive franchise to the Tulare Canal and Land Company (sometimes known as the Montgomery franchise, after two of the firm's founders). The company's purpose was to connect navigable canals from the southern San Joaquin Valley to the San Joaquin River, which entered from the Sierra Nevada about half way up the valley. That stream, in turn, joined with San Francisco Bay, and thus the canals would open the entire San Joaquin Valley to world-wide commerce. In exchange for building the canals, the Montgomery franchise could collect tolls for twenty years and sell half the drained swamplands (the other half was to be sold by the state). Land sales were contingent upon the Montgomery franchise reclaiming the marshes. Wetlands in the mid-nineteenth century were not viewed as they are today as fragile wildlife habitats but instead as impediments to advancing American ideals and homesteads across the continent. Moreover, marshy areas were seen as major health menaces, with the prevailing view being that swampy regions’ air carried infectious diseases.

Loa Kulu minapolitan is an area producing land fisheries products in Kutai Kartanegara Regency, Indonesia. The demand for fishery products both within and outside this region is continuously increasing. However, intensification efforts seem to unable to fulfill market demand. Furthermore, the efforts are constrained by information unavailability for aquaculture potential land. Land detection for inland waters in research location is the first step to provide manageable water land to increase fisheries production in this region. This paper is preliminary research aimed to draw an existing map of inland waters distribution at the research site. Google image interpretation and field observations techniques are used to detect the spatial distribution of inland waters. Moreover, the methods for validation processes or data accuracy are point sampling and area sampling accuracy. The analysis results of point sampling accuracy in this study were 80.99% (acceptable result). The percentage of bias at point sampling accuracy is 19.01% (acceptable result). Total bias value which is caused by differences in time taken for two data types. Besides, the object size is smaller than the image resolution ability. While the results of the area sampling accuracy in this study indicate that swampland use has an accuracy of 100%, rice fields 99.91% and rivers 99.50% (acceptable result). In conclusion, study result is considered relevant to be the initial description of inland waters distribution map as an input for research on determining potential land for inland aquaculture development to increase fisheries production at the research site.

Iron toxicity is the main problem in using acid sulfate soils for growing rice, as it decreases its agronomic traits. The experiment aimed (1) to study the effects of Fe concentrations on some agronomic traits of 15 improved rice varieties and (2) to find varieties that are tolerant to iron toxicity in acid sulfate soils of tidal swampland. The experiment was conducted in the greenhouse of Indonesian Swampland Agricultural Research Institute, Banjarbaru, Indonesia, and made use of Factorial Randomized Completely Design with three replications. The first factor was 15 improved rice varieties, and the second was four Fe concentrations of acid sulfate soils (229.44; 236.34; 564.15, and 1277.50 mg kg-1 Fe). Furthermore, observation variables included plant growth (plant height, tiller number, root and straw dry weight), grain yield, harvest index, and iron toxicity symptoms. The results showed that an increase in Fe concentrations of acid sulfate soils led to a decrease in rice agronomic traits (maximum tiller number, plant height, dry weight of roots and straw, grain yield and harvest index), but an increase in iron toxicity symptoms. Varieties Inpara-1 and Inpara-2 revealed the smallest decrease in rice agronomic traits and exhibited the lightest iron toxicity symptoms, whereas IR64 showed the greatest decrease in the traits and the most severe symptoms. Inpara-1 and Inpara-2 were identified as the varieties tolerant to iron toxicity in the acid sulfate soils of tidal swampland.