Definition of universe
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Definition of Universe: A Comprehensive Overview
Universe in Physical Cosmology
In physical cosmology, the universe is often defined as the totality of everything that exists, encompassing all physical matter, energy, planets, stars, galaxies, and the contents of intergalactic space. This definition aligns with the prevailing scientific model known as the Big Bang theory, which posits that the universe expanded from an extremely hot, dense phase called the Planck epoch7. The universe continues to expand, and it is believed to be mostly composed of dark energy and dark matter, both of which remain poorly understood7.
Universe as a Spacetime Box
Another perspective defines the universe as the contents of a spacetime box with comoving walls, large enough to contain measurable phenomena but not much larger. This approach allows for the construction of a local ensemble of such universes, assuming that similar universes can be constructed further out with different standard model parameters1. This definition helps in understanding the hierarchy problems of particle physics and suggests that theories of the multiverse may eventually be scientifically validated1.
Philosophical and Semantic Perspectives
Philosophically, the concept of the universe has been debated extensively. Some argue that the term "universe" is not a genuine singular term and cannot name a single, completely encompassing individual or a collection of individuals. Instead, it stands equally for every existing object2. This view contrasts with the traditional notion of the universe as the entire reality, which often leads to logical contradictions4. The realist interpretation of the universe's global properties is problematic because it leads to unstable conclusions, making the universe as a whole empirically inaccessible4.
Universe in Advanced Practice Nursing
In the context of nursing research and practice, the universe is defined as all physical matter, including stars, planets, galaxies, and everything within them, such as human beings and nature. This broad concept emphasizes the connection and interconnection of the universe in its entirety to human beings and healthcare5. Attributes of the universe include human beings, the environment, and cognition, with consequences such as self-awareness, evolution, and support5.
Multiverse and Universe Classification
The concept of a multiverse suggests that multiple universes exist, each with its own properties. A standardized definition for member universes similar to our own includes the size, taken as the asymptotic value of the inverse Hubble constant at large times. This definition implies that vacuum parameters and coupling constants of the standard model depend on the size of a universe, with anthropic considerations limiting the size of habitable universes8.
Historical and Etymological Insights
Historically, the term "universe" is derived from the Latin "unus" (one) and "versus" (turned), meaning "turned or combined into one." It is defined as all created things constituting one system, synonymous with the cosmos9. This definition underscores the universe as an orderly and harmonious system, contrasting with chaos9.
Conclusion
The definition of the universe varies across different fields, from physical cosmology and particle physics to philosophy and nursing. While the scientific community often views the universe as the totality of all physical matter and energy, philosophical perspectives challenge the singularity and comprehensiveness of the term. The concept of a multiverse further complicates the definition, suggesting multiple universes with varying properties. Despite these differing views, the universe remains a central concept in understanding the nature of existence and our place within it.
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