59,809 research outputs found
Initial directional singularity in inflationary models
In [1] a new cosmological model is proposed with no big bang singularity in
the past, though past geodesically incomplete. This model starts with an
inflationary era, follows with a stiff matter dominated period and evolves to
accelerated expansion in an asymptotically de Sitter regime in a realistic
fashion. The big bang singularity is replaced by a directional singularity.
This singularity cannot be reached by comoving observers, since it would take
them an infinite proper time lapse to go back to it. On the contrary, observers
with nonzero linear momentum have the singularity at finite proper time in
their past, though arbitrarily large. Hence, the time lapse from the initial
singularity can be as long as desired, even infinity, depending on the linear
momentum of the observer. This conclusion applies to similar inflationary
models. Due to the interest of these models, we address here the properties of
such singularities.Comment: RevTeX, 11 pages, typos correcte
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Private Health Insurance Market Reforms in the Affordable Care Act (ACA)
[Excerpt] This report provides background information about the private health insurance market, including market segments and regulation. It then describes each ACA market reform. The reforms are grouped under the following categories: obtaining coverage; keeping coverage; cost of purchasing coverage; covered services; cost-sharing limits; consumer assistance and other health care protections; and plan requirements related to health care providers. The Appendix of the report provides details about the types of plans that are required to comply with the different reforms
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Private Health Plans Under the ACA: In Brief
[Excerpt] The Patient Protection and Affordable Care Act (ACA, P.L. 111-148), as amended, expands federal private health insurance market requirements, and requires the creation of health insurance exchanges (marketplaces) to provide certain individuals and small employers access to private insurance, among other provisions. While some of ACA’s private insurance provisions have already become effective, full implementation begins in 2014 and beyond. Given the breadth of ACA’s reforms to the existing private insurance market and creation of new health insurance marketplaces, there is interest in understanding what types of health plans may be offered once these ACA provisions are fully implemented.
This report provides short descriptions of health plans that may be offered inside and outside of exchanges, and includes information about interaction with other selected ACA provisions. The descriptions are displayed in a side-by-side format to facilitate comparison of exchange and non- exchange plans. This report does not attempt to identify all forms of health insurance coverage, but does address all plan types specified under ACA’s exchange provisions, as well as major medical plans and certain limited benefit plans offered outside of exchanges. In addition, this report indicates the applicability of ACA’s market reforms to plans offered in the private market
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Private Health Insurance Market Reforms in the Patient Protection and Affordable Care Act (ACA)
[Excerpt] The private health insurance provisions in the Patient Protection and Affordable Care Act (P.L. 111-148, ACA, as amended) include market reforms that impose requirements on private health insurance plans. Such reforms relate to the offer, issuance, generosity, and pricing of health plans, among other requirements.
This report provides background information about the private health insurance market, including market segments and regulation. It describes each ACA market reform and notes any major implementation activity that has occurred (e.g., issuance of final rule from a department such as Health and Human Services). The appendices of the report provide additional information about the status of regulations relating to each reform and how the reforms apply to the different market segments and health plans
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Cancellation of Nongroup Health Insurance Policies
Congress has expressed interest in health insurance cancellations, in light of media reports stating that individuals have received cancellation letters. While cancellations are not a new industry practice, additional attention has focused on the more recent cancellations given that many of the insurance market reforms included in the Patient Protection and Affordable Care Act (ACA, P.L. 111-148, as amended) will become effective beginning in 2014. These cancellations and proposals to address them, including the Administration’s recently announced transitional policy, have been discussed in recent hearings and are the subject of legislative proposals.
This report provides background information about health insurance cancellations, non-renewals and rescissions, including applicable federal rules under the Health Insurance Portability and Accountability Act of 1996 (HIPAA) and ACA. Given that the concern about insurance cancellations has largely focused on the nongroup market, this report discusses federal requirements and implementation issues that apply to nongroup coverage
Cosmological singularities in FLRW spacetimes
In this talk we review the appearance of new types of singularities (big rip,
sudden singularities...) in FLRW cosmological models that have arisen on
considering explanations for accelerated expansion of our universe.Comment: 3 pages, ws-procs975x65.cls to appear in Proceedings of 12th Marcel
Grossmann Meeting, Pari
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Health Insurance Exchanges Under the Patient Protection and Affordable Care Act (ACA)
[Excerpt] A health insurance exchange is a structured marketplace for the sale and purchase of health insurance. “Customers” can include individuals and businesses. The insurance companies (“issuers”) that choose to sell their products through an exchange may be required to comply with consumer protections, such as offering insurance to every qualified applicant. Exchanges, however, are not issuers; rather, exchanges contract with issuers who will make insurance products available for purchase through exchanges. Essentially, exchanges are designed to bring together buyers and sellers of insurance, with the goal of increasing access to coverage.
This rather broad definition allows for a great deal of latitude, and therefore variance, in the number and scope of responsibilities covered in a particular exchange. For example, the role of an exchange may be more or less administrative: facilitating the sale and purchase of health insurance. An administrative-only exchange may function similar to websites that allow individuals to find airline travel options and purchase tickets (e.g., Kayak). Such an approach does not necessarily change or establish standards for the products being sold (whether they are health plans or airline tickets), or limit the types of buyers and sellers participating in the exchange, beyond what already exists in the private market. An example of a minimalist health insurance exchange is the Utah Health Exchange. Essentially, Utah’s exchange is an Internet portal that is “designed to connect consumers to the information they need to make informed health care choices, and in the case of health insurance, to execute that choice electronically.”
At the other end of the spectrum, an exchange may have multiple functions beyond the role of insurance marketplace. For instance, an exchange may be responsible for implementing regulatory standards, such as requiring standardization of all products offered through it or imposing requirements on exchange participants. An exchange may be responsible for determining eligibility for exchange plans and government-provided subsidies. An example of a more regulatory-oriented exchange is the Health Connector (“Connector”) in Massachusetts. Similar to Utah’s exchange, the Connector provides an online tool to allow consumers and others to find commercial health insurance options available to them. In addition, the Connector also manages a publicly subsidized coverage program for low-income state residents, and offers certificates to exempt individuals from the state’s individual mandate, among other duties.
An exchange may occupy a physical location and/or be virtual (i.e., performing its functions on the Internet). It may be governed by a public agency, a private entity, or a hybrid organization. The insurance options offered through an exchange may also vary across insurance markets and plan types. Nonetheless, while the authority and responsibilities of an exchange may vary, its fundamental purpose is to provide a venue where insurance companies may sell their insurance products and purchasers can compare and choose from multiple options available to them. Thus an exchange allows for “one-stop shopping” with respect to health insurance.
The exchange concept was included in the Patient Protection and Affordable Care Act (ACA, P.L. 111-148, as amended), as a means to increase access to health insurance. While ACA places many restrictions on the design and function of exchanges, the law also leaves many operational decisions to the states. Such flexibility will likely lead to variation in exchange models across the states. For example, a state may decide to operate an exchange by itself, establish an exchange in partnership with the federal government, or leave this work entirely to the federal government. States had to declare whether they will have a state exchange by December 14, 2012. By February 15, 2013, states must declare whether they will operate an exchange in partnership with the federal government. The initial open enrollment period for all exchanges will begin on October 1, 2013, and all exchanges are to be operational and offering coverage on January 1, 2014.
This report looks at the requirements for exchanges established in ACA and provides information on the requirements and choices available to states for the establishment, functions, financial responsibilities, and coverage of the ACA exchanges. It also includes a brief discussion of the interactions between exchanges and other provisions in the law
Mean-value identities as an opportunity for Monte Carlo error reduction
In the Monte Carlo simulation of both Lattice field-theories and of models of
Statistical Mechanics, identities verified by exact mean-values such as
Schwinger-Dyson equations, Guerra relations, Callen identities, etc., provide
well known and sensitive tests of thermalization bias as well as checks of
pseudo random number generators. We point out that they can be further
exploited as "control variates" to reduce statistical errors. The strategy is
general, very simple, and almost costless in CPU time. The method is
demonstrated in the two dimensional Ising model at criticality, where the CPU
gain factor lies between 2 and 4.Comment: 10 pages, 2 tables. References updated and typos correcte
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