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In the vast expanse of the cosmos, two mysterious and enigmatic phenomena, dark energy and dark matter, hold sway over the universe's evolution. Both concepts emerge from the frontiers of modern cosmology and particle physics, challenging our understanding of the fundamental nature of the cosmos. While they share the common prefix "dark," indicating their invisibility to conventional telescopes, dark energy and dark matter exhibit starkly different behaviors and play distinct roles in the cosmic drama. Dark matter, a concept rooted in early 20th-century astrophysics, arises from observations of the gravitational dynamics of galaxies and galaxy clusters. Unlike ordinary matter, which interacts electromagnetically and emits or absorbs light, dark matter remains invisible, interacting only through gravity and potentially other weak forces. Its presence is inferred from its gravitational effects on visible matter, such as stars and galaxies, as well as on light itself. One of the most compelling pieces of evidence for dark matter's existence comes from the rotational speeds of galaxies. Observations reveal that stars in the outer regions of galaxies orbit at velocities inconsistent with the visible mass alone. The presence of unseen, or "dark," matter provides the additional gravitational pull necessary to explain these observations. Similarly, gravitational lensing phenomena, where the path of light is bent by massive objects, further support the notion of pervasive dark matter halos surrounding galaxies. On the other hand, dark energy represents a more recent and perplexing discovery, emerging from observations of distant supernovae in the late 1990s. Unlike dark matter, which acts as a gravitational attractor, dark energy behaves as a repulsive force, driving the accelerated expansion of the universe. This revelation defied previous assumptions that gravity should slow down the cosmic expansion over time. Instead, dark energy's presence implies a cosmic antigravity, pushing galaxies apart at an ever-increasing rate. The nature and origin of dark energy and dark matter remain subjects of intense speculation and investigation. Dark matter is often theorized to consist of Weakly Interacting Massive Particles (WIMPs) or other exotic particles beyond those of the Standard Model of particle physics. Numerous experiments have been conducted in search of these hypothetical particles, yet direct detection has remained elusive. Similarly, the identity of dark energy remains one of the most significant puzzles in contemporary cosmology. Some theories propose that dark energy may be a property of space itself, represented by a cosmological constant or vacuum energy. Others suggest the existence of dynamic scalar fields, such as quintessence, driving the accelerated expansion. Despite their differences, dark energy and dark matter represent fundamental challenges to our understanding of the cosmos. Their elusive nature, coupled with their profound influence on the universe's structure and evolution, continues to drive scientific inquiry and exploration. Unraveling the mysteries of dark energy and dark matter promises not only to deepen our understanding of the universe but also to shed light on the fundamental laws governing its existence.

The universe is an unimaginably large and continues to expand till the end of time. But that does not mean that the universe can be destroyed beforehand. Meet the starngelets as strange as they sound! Neutron Star A neutron star is a very dense and compact star composed mainly of neutrons12.It is the remnant of the core of a massive star that exploded as a supernova.Neutron stars are typically about 20 km in diameter and have masses between 1.18 and 1.97 times that of the Sun.They are one of the possible outcomes of the evolution of the most massive stars, along with black holes. These neutron stars have a core like the stars which contain the weirdest thing in the universe and the self destruct button of it. Strange Matter Strange matter is a soup-like substance made of a trio of quarks, including strange quarks . It is unlike any matter on Earth, as it is heavier and less organized.It is speculated to exist in the core of neutron stars, or as isolated droplets called strangelets or strange stars. Some physicists have suggested that strange matter could turn ordinary matter into strange matter if they come into contact, potentially destroying the world. When was it created? After 0.32 seconds since the big bang, quarks- things found inside protons and neutrons which is the smallest particle in existence were tightly clumped together in a hot area, this created strangelets or stramge matter. When two quarks collided by the high pressure strange matter was formed. This strange matter engulfed more quarks causing the first neutrons stars to form. How could they destroy the universe? For example, if a strangelet (large as a neucleus of a oxygen atom) touched earth, then it will shrink 1/7 of its size and become very dense and becomes the hazardous strange matter. If a strangelet hits the Sun, then it will become twice the size of uranus and become strange matter. Information about the strange matter. Strange quarks or strangelets are not made of any atom, just a few quarks in a huge temperature three times higher than the boiling point of water. It cannot turn a gas or light into strange matter. That is everything known about the destruct button of the universe or strange matter. As of November 2023.

BLACK HOLES This is everything you need to know about a black hole and its limitation, nature and how to escape it. ACCRETION DISK A thick accretion disk has formed around a black hole following the destruction of a star that wandered too close . Stellar debris has fallen toward the black hole and collected into a thick chaotic disk of hot gas. A thin jet of high-speed particles emerges from just above the black hole. Accretion disks also form around newborn stars. These emit lower-energy infrared light. Planets form from the dust in the disks around stars.The study of oscillation modes in accretion disks is referred to as diskoseismology ( diss-koses-mau-lau-gy). Accretion disks are a universal phenomenon in astrophysics; active galactic nuclei, protoplanetary disks, and gamma ray bursts all involve accretion disks. These disks very often give rise to astrophysical jets coming from the vicinity ( in other words jets coming from the central part )of the central object. Jets are an efficient way for the star-disk system to shed angular momentum without losing too much mass. The most spectacular accretion disks found in nature are those of active galactic nuclei and of quasars, which are massive black holes at the center of galaxies. As matter enters the accretion disc, it follows a trajectory called a tendex line, which describes an inward spiral. This is because particles rub and bounce against each other in a steady flow, causing frictional heating which radiates energy away, reducing the particles' angular momentum, allowing the particle to drift inward, driving the inward spiral. PHOTONOSPHERE The photon sphere is located farther from the center of a black hole than the event horizon. Within a photon sphere, it is possible to imagine a photon (a particle representing a quantum of light or other electromagnetic radiation.) that's emitted from the back of one's head, orbiting the black hole, only then to be intercepted by the person's eyes, allowing one to see the back of the head. This might sound pretty cool but is very disruptive. A rotating black hole has two photon spheres. As a black hole rotates, it drags space with it. The photon sphere that is closer to the black hole is moving in the same direction as the rotation, whereas the photon sphere further away is moving against it. The greater the angular velocity of the rotation of a black hole, the greater the distance between the two photon spheres. Since the black hole has an axis of rotation, this only holds true if approaching the black hole in the direction of the equator. Not much is known about the photon sphere and has some large calculations behind the scenes, so next is the ergosphere. ERGOSPHERE The ergosphere is a region outside of the outer event horizon. In the ergosphere the rotating Black Hole drags space around with it (called frame dragging) in such a way that all objects inside the ergosphere must rotate with the Black Hole. No time-like curves exist that go in the opposite direction.As a black hole rotates, it twists spacetime in the direction of the rotation at a speed that decreases with distance from the event horizon. This process is known as the Lense–Thirring effect or frame-dragging. Because of this dragging effect, an object within the ergosphere cannot appear stationary with respect to an outside observer at a great distance unless that object were to move at faster than the speed of light (an impossibility) with respect to the local spacetime. The speed necessary for such an object to appear stationary decreases at points further out from the event horizon, until at some distance the required speed is negligible. EVENT HORIZON The event horizon is the spherical outer boundary of a black hole loosely considered to be its "surface." It is the point, according to NASA, that the gravitational influence of the black hole becomes so great that not even light is fast enough to escape it.One of the leading developers of theories to describe black holes, Stephen Hawking, suggested that an apparent horizon should be used instead of an event horizon, saying, "Gravitational collapse produces apparent horizons but no event horizons." He eventually concluded that "the absence of event horizons means that there are no black holes – in the sense of regimes from which light can't escape to infinity." Any object approaching the horizon from the observer's side appears to slow down, never quite crossing the horizon.f a particle is moving at a constant velocity in a non-expanding universe free of gravitational fields, any event that occurs in that Universe will eventually be observable by the particle, because the forward light cones from these events intersect the particle's world line. On the other hand, if the particle is accelerating, in some situations light cones from some events never intersect the particle's world line. Under these conditions, an apparent horizon is present in the particle's (accelerating) reference frame, representing a boundary beyond which events are unobservable. SINGULARITY According to General Relativity, inside of a black hole, there must be a region of infinite density at its center: commonly referred to as a singularity. But singularities are pathological in mathematical terms: it's as though you divided by zero, and everything becomes ill-defined. Gravitational singularities are mainly considered in the context of general relativity, where density would become infinite at the center of a black hole without corrections from quantum mechanics, and within astrophysics and cosmology as the earliest state of the universe during the Big Bang. Physicists are undecided whether the prediction of singularities means that they actually exist (or existed at the start of the Big Bang), or that current knowledge is insufficient to describe what happens at such extreme densities. WHITE HOLES In general relativity, a white hole is a hypothetical region of spacetime and singularity that cannot be entered from the outside, although energy-matter, light and information can escape from it. In this sense, it is the reverse of a black hole, from which energy-matter, light and information cannot escape. White holes appear in the theory of eternal black holes. In addition to a black hole region in the future, such a solution of the Einstein field equations has a white hole region in its past. This region does not exist for black holes that have formed through gravitational collapse, however, nor are there any observed physical processes through which a white hole could be formed. Supermassive black holes (SMBHs) are theoretically predicted to be at the center of every galaxy and that possibly, a galaxy cannot form without one. Stephen Hawking and others have proposed that these supermassive black holes spawn a supermassive white hole. HAWKING RADIATION Hawking radiation is the theoretical thermal black-body radiation released outside a black hole's event horizon. This is counterintuitive because once ordinary electromagnetic radiation is inside the event horizon, it cannot escape. It is named after the physicist Stephen Hawking, who developed a theoretical argument for its existence in 1974. Hawking radiation is predicted to be extremely faint and is many orders of magnitude below the current best telescopes' detecting ability. Hawking radiation reduces the mass and rotational energy of black holes and is therefore also theorized to cause black hole evaporation. Because of this, black holes that do not gain mass through other means are expected to shrink and ultimately vanish.For all except the smallest black holes, this happens extremely slowly. HOW TO ESCAPE A BLACK HOLE In summary, escaping from a black hole is currently not possible using our current technology and understanding of physics. The extreme gravitational forces and warping of space-time make it impossible for any object to escape from within the event horizon. So for some time, no human-black hole sattelite will be launched unless of some flaw in Hawking's theories.