01 July 2023

The anti-gravitational effect observed in galaxies...

The anti-gravitational effect observed in galaxies and their drift leads to the concept of a mysterious energy called dark energy. Dark energy is usually described by w ≡ P/ρ, where P and ρ denote its pressure and energy density. Dark Energy is un-massive, roughly 10¯²⁷ kg/m³. Dark energy causes repulsive gravity through negative internal pressure. (10¯²⁷ = 0.000000000000000000000000001).


Dark energy is often described by its equation of state parameter, denoted as "w," which is the ratio of its pressure (P) to its energy density (ρ). Dark energy is characterized by a negative pressure, which results in a repulsive gravitational effect, driving the observed accelerated expansion of the universe.

The equation of state parameter w for dark energy is typically close to -1, indicating that the pressure is negative and its magnitude is equal to the energy density. This negative pressure counteracts the attractive gravitational force of matter, leading to the expansion of the universe becoming accelerated.

The energy density of dark energy is estimated to be around 10¯²⁷ kg/m³. It is an extremely low density compared to other forms of energy in the universe, such as matter and radiation. Despite its low density, dark energy is thought to dominate the total energy content of the universe at present, comprising about 70% of the total energy density.

The exact nature and origin of dark energy are still not well understood, and it remains an active area of research in cosmology and theoretical physics. The term "dark energy" is a placeholder for the unknown source of the observed accelerated expansion, and its precise composition and underlying physical mechanism are subjects of ongoing investigation.

__________________________________________

Dark energy is often described by the parameter w, which represents the ratio of its pressure (P) to its energy density (ρ). Mathematically, it is defined as w ≡ P/ρ. Dark energy is characterized by a negative pressure, meaning that it behaves in a repulsive manner, counteracting the attractive gravitational force due to matter and causing the accelerated expansion of the universe.

The exact nature of dark energy is still a mystery, and its physical origin is not well understood. One of the leading candidates for dark energy is the cosmological constant, represented by the Greek letter lambda (Λ), which is often associated with vacuum energy. The cosmological constant is a constant energy density that permeates space, leading to a negative pressure and driving the accelerated expansion of the universe.

The energy density of dark energy is roughly 10⁻²⁷ kg/m³, making it extremely diffuse compared to other forms of energy and matter in the universe. Despite its low density, dark energy is believed to dominate the energy budget of the universe at present, accounting for about 68% of the total energy content, while dark matter makes up about 27%, and ordinary matter (baryonic matter) constitutes only about 5%.

The existence of dark energy and its role in the accelerated expansion of the universe were discovered through observations of distant supernovae and other cosmological probes, such as the cosmic microwave background radiation. The discovery of dark energy has been one of the most significant and intriguing findings in modern cosmology, and understanding its nature remains a fundamental challenge for theoretical physics.

Acknowledgement:
The author of this Bolg expresses his sincere gratitude for significant help in the creation of this article, and so gives most credit to ChatGPT that significantly contributed to the content of this article.

29 June 2023

Why there is accelerated expansion in the distance among galaxies?

Abstract:

The accelerated expansion of the universe is explained by the Friedmann equation, derived from Einstein's field equations in general relativity. This equation relates the rate of expansion (Hubble parameter), energy density of universe components (such as matter, radiation, and dark energy), and the geometry of space. The simplified Lambda-CDM model incorporates dark energy effects, resulting in a more accurate understanding of the universe's expansion.

Energy conversion corresponding to time dilation in question:

[Author ORCID: 0000-0003-1871-7803] 

Time is not considered a form of mass or energy, and mass or energy cannot be transformed directly into time. In physics, time is considered a fundamental dimension or parameter in which events occur. It is often treated as an independent concept that is separate from mass and energy.

In a fixed frame of reference, energy is not covariant but invariant.

However, the Lorentz transformation implies that energy can change when one moves from one reference frame to another, hence, energy is covariant between reference frames.

While logically and physically, the Lorentz transformation is the space-time transformation of special relativity.

According to relativistic law, energy and momentum are transformed under Lorentz transformation.

Therefore, according to the above messages time dilation is a consequence between two reference frames which corresponds to energy conversion.

However, time, whether proper time or relativistic time, is not a form of mass or energy, so mass or energy cannot be transformed into time, as per the law of conservation of energy.

Therefore, this physical and mathematical observation raises deep questions about the validity of relativistic time dilation with the application of the Lorentz transformation.

Reference https://physics.stackexchange.com/questions/364152/energy-conservation-violation

Alternative Source: Energy and momentum are transformed under the Lorentz transformation in special relativity. The Lorentz transformation describes how physical quantities, including energy and momentum, change when transitioning between different inertial reference frames that are moving relative to each other.

Time dilation is indeed a consequence of relative motion between two reference frames. When an observer is in relative motion with respect to another observer, they will perceive time to be dilated or stretched out compared to the stationary observer. This means that the moving observer's clock will appear to run slower from the perspective of the stationary observer.

The relationship between time dilation and energy can be understood within the framework of special relativity. As an object moves relative to an observer, its energy and momentum are transformed according to the Lorentz transformation. This transformation includes a factor known as the time dilation factor, which is related to the relative velocity between the two frames. The change in energy observed between reference frames can be attributed to the time dilation effect.

Therefore, this physical and mathematical observation raises deep questions about the validity of relativistic time dilation with the application of the Lorentz transformation. 

#covariantenergy #invariantenergy #Lorentztransformation 

Link, describing The Friedmann equation :

The Friedmann equation includes the Hubble constant to give a much more accurate age of the Universe. In this equation, G is the gravitational constant = 6.67*10-11Nm2/kg2, ρr is the radiation density of the universe, ρm is the matter density of the universe, and ρd is the dark energy density of the universe.


https://www.phys.ksu.edu/personal/rprice/Friedmann.pdf

Dark energy and Dark matter in simple terms:

Dark Energy: Simply put, the anti-gravitational effect observed in galaxies and their drift leads to the concept of a mysterious energy called dark energy. Dark energy is usually described by w ≡ P/ρ, where P and ρ denote its pressure and energy density. Dark Energy is un-massive, roughly 10¯²⁷ kg/m³Dark energy causes repulsive gravity through negative internal pressure.

10¯²⁷ = 0.000000000000000000000000001

Dark Matter: In the simplest terms, the observed extra-gravitational effects on galaxies and their similar behavior, such as unaccounted rotation, lead to the idea of an invisible mass effect called dark matter.

#darkmatter #darkenergy .