This document discusses black holes and provides information on their structure, types, behavior, and formation. It describes how black holes have intense gravity that prevents even light from escaping once it passes the event horizon. The document also discusses famous black holes like Cygnus X-1 and Sagittarius A*, the supermassive black hole at the center of the Milky Way galaxy. Stephen Hawking's theory that black holes emit radiation and glow is also summarized.
Hey I'm DIVYA SHREE NANDINI. I'm here with my new presentation on Black Hole. I'm sure you'll find it interesting. well first thing what is black hole- "Black hole, cosmic body of extremely intense gravity from which nothing, not even light, can escape. A black hole can be formed by the death of a massive star. When such a star has exhausted the internal thermonuclear fuels in its core at the end of its life, the core becomes unstable and gravitationally collapses inward upon itself, and the star’s outer layers are blown away. The crushing weight of constituent matter falling in from all sides compresses the dying star to a point of zero volume and infinite density called the singularity." wanna know more about it then come with me. :)
"Black holes are where God divided by zero" - Albert Einstein
Black hole – A region in the space where the gravitational pull is so strong that neither substance nor light can leave this area.
Hey I'm DIVYA SHREE NANDINI. I'm here with my new presentation on Black Hole. I'm sure you'll find it interesting. well first thing what is black hole- "Black hole, cosmic body of extremely intense gravity from which nothing, not even light, can escape. A black hole can be formed by the death of a massive star. When such a star has exhausted the internal thermonuclear fuels in its core at the end of its life, the core becomes unstable and gravitationally collapses inward upon itself, and the star’s outer layers are blown away. The crushing weight of constituent matter falling in from all sides compresses the dying star to a point of zero volume and infinite density called the singularity." wanna know more about it then come with me. :)
"Black holes are where God divided by zero" - Albert Einstein
Black hole – A region in the space where the gravitational pull is so strong that neither substance nor light can leave this area.
It is said that fact is sometimes stranger than fiction, and nowhere is this more true than in the case of black holes. Black holes are stranger than anything dreamt up by science fiction writers, but they are firmly matters of science ~fact.
This is a presentation on Black Holes.
This covers following data about Black Hole->
>>What is Black Hole.
>>History.
>>Parts of Black Hole.
>>Classification.
>>Closest Black Hole.
>>Largest Black Hole.
search on NASA site also go through the latest news related to black holes before presenting your seminar.
many queries are asked related to black holes.
present the astronomical data's for Good delivery of seminar.In the 18th century John Michell and Pierre-Simon Laplace first mentioned about the objects with a huge gravitation, from which even light cannot escape.
In 1915 Albert Einstein developed the theory of general relativity.
Karl Schwarzschild finds black holes as a solution to Einstein’s equations (1916)
Robert Oppenheimer and Hartland Snyder predict that massive stars can collapse into black holes (1939)
A black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull.”
Black holes are exotic structures whose gravitational fields are so powerful that they trap everything, even light. They were first postulated by Albert Einstein's theory of general relativity.”
This can happen when a star is dying.
Though they are black they are invisible to us.
The density of a black hole is so great it would be like taking the whole Earth and crushing into a volume smaller than a 1” marble!.
Stellar-mass: 3 to 20 times the mass of our Sun
Supermassive: Black holes with millions to billions of times the mass of our Sun
Mid-mass: In between stellar-mass and supermassive.
A presentation I gave to the Brighton Astronomy Society in Jan 2016 - http://brightonastro.com/ , https://www.facebook.com/brightonastro/
Annoyingly that's removed the videos from the slides, so here are links to those:
https://www.youtube.com/watch?v=e-P5IFTqB98&t=18s
(This Youtube channel "In a nutshell" is absolutely fantastic by the way and I highly recommend a look through their other videos!)
https://www.youtube.com/watch?v=duoHtJpo4GY
https://vimeo.com/8723702
I've also made my notes from preparing the slides available here as well:
https://docs.google.com/document/d/1gqgsAbvoCB_7-_gPToqOuSixc02YnU-ajf-uT60R1vc/edit?usp=sharing
-- there are LOTS of further links to interesting videos in there as well, that I didn't use on the night so worth a scan through.
Any further questions, feel free to ask in comments on here
It is said that fact is sometimes stranger than fiction, and nowhere is this more true than in the case of black holes. Black holes are stranger than anything dreamt up by science fiction writers, but they are firmly matters of science ~fact.
This is a presentation on Black Holes.
This covers following data about Black Hole->
>>What is Black Hole.
>>History.
>>Parts of Black Hole.
>>Classification.
>>Closest Black Hole.
>>Largest Black Hole.
search on NASA site also go through the latest news related to black holes before presenting your seminar.
many queries are asked related to black holes.
present the astronomical data's for Good delivery of seminar.In the 18th century John Michell and Pierre-Simon Laplace first mentioned about the objects with a huge gravitation, from which even light cannot escape.
In 1915 Albert Einstein developed the theory of general relativity.
Karl Schwarzschild finds black holes as a solution to Einstein’s equations (1916)
Robert Oppenheimer and Hartland Snyder predict that massive stars can collapse into black holes (1939)
A black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull.”
Black holes are exotic structures whose gravitational fields are so powerful that they trap everything, even light. They were first postulated by Albert Einstein's theory of general relativity.”
This can happen when a star is dying.
Though they are black they are invisible to us.
The density of a black hole is so great it would be like taking the whole Earth and crushing into a volume smaller than a 1” marble!.
Stellar-mass: 3 to 20 times the mass of our Sun
Supermassive: Black holes with millions to billions of times the mass of our Sun
Mid-mass: In between stellar-mass and supermassive.
A presentation I gave to the Brighton Astronomy Society in Jan 2016 - http://brightonastro.com/ , https://www.facebook.com/brightonastro/
Annoyingly that's removed the videos from the slides, so here are links to those:
https://www.youtube.com/watch?v=e-P5IFTqB98&t=18s
(This Youtube channel "In a nutshell" is absolutely fantastic by the way and I highly recommend a look through their other videos!)
https://www.youtube.com/watch?v=duoHtJpo4GY
https://vimeo.com/8723702
I've also made my notes from preparing the slides available here as well:
https://docs.google.com/document/d/1gqgsAbvoCB_7-_gPToqOuSixc02YnU-ajf-uT60R1vc/edit?usp=sharing
-- there are LOTS of further links to interesting videos in there as well, that I didn't use on the night so worth a scan through.
Any further questions, feel free to ask in comments on here
Journey Through the Cosmos: Exploring Black Holes & Dr. Stephen Hawking's Leg...TUHIN SAHA
Title: Journey Through the Cosmos: Exploring Black Holes & Dr. Stephen Hawking's Legacy
Embark on a captivating journey through the depths of space and the brilliant mind of one of history's most renowned scientists, Dr. Stephen Hawking. In this enlightening presentation, we delve into the enigmatic phenomenon of Black Holes, their mysterious nature, and the groundbreaking discoveries that have shaped our understanding of the universe.
Unlock the secrets of these celestial wonders as we explore topics such as the fundamental question: What is a Black Hole? Delve into the gripping tale of their discovery and unravel the intricate process of their formation. From the mind-bending structure of Black Holes to the various types that exist across the cosmos, each slide unveils a new layer of cosmic intrigue.
But what happens if someone were to venture too close, falling into the gravitational abyss of a Black Hole? Discover the scientific speculation and theories that surround this captivating scenario, offering insight into the ultimate fate of such an intrepid explorer.
Moreover, journey through the extraordinary life and groundbreaking research of Dr. Stephen Hawking, a visionary whose contributions to theoretical physics revolutionized our understanding of the cosmos. Explore the trials and triumphs of his remarkable journey, from his early years to his groundbreaking work on Black Holes and beyond.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
2. CONTENTS:
Introduction
Historical Background
Structure Of Black Holes
Types Of Black Holes
Light Behavior Near Black Holes
Facts About Black Holes
Milky Way Galaxy
Famous Black Holes
Formation And Growth Of Black Holes
Stephen William Hawking’s Theory
How To Locate Black Holes
Controversy About Black Holes
3. INTRODUCTION:
Black holes are among the strangest
things in the universe. They are massive
objects with gravity so strong that
nothing can escape, not even light.
They are called black holes because even
light cannot pass or reflect from them and
they absorb all the light hitting them.
4. HISTORICAL BACKGROUND:
The idea of a body so massive that even light cannot escape from it was put
forwarded by a geologist John Michel in a letter written to Henry Cavendish in
1783 to the Royal Society.
In 1939, American physist Robert Oppenheimer developed a possible
explanation for the these points of infinite density.
These theories remained a mathematical curiosity until the first black hole
was found in 1964.
In 2006, Stephen Hawking proposed that microscopic black holes are formed
in the huge explosion that gave birth to universes.
5. STRUCTURE OF BLACK HOLES:
Singularity:
The point where whole mass of a black hole
is concentrated.
Photon Sphere:
The outer edge where light bends but is still
escapable.
Event Horizon:
It is a “point of no return” around a black
hole.
Accretion Disk:
It is a disk of gases, dust, stars and planets
that fall into the orbit of a black hole.
6. TYPES OF BLACK HOLES:
Stellar-mass Black Holes:
Stellar-mass black holes are created when massive stars explode,
leaving behind a black hole with the mass of just a few suns.
Supermassive Black Holes:
Supermassive black holes exist in the hearts of galaxies and
usually contain the mass equivalent to millions and billions of suns.
Intermediate Black Holes:
Such bodies could form when stars collide in a chain reactions and
usually contain the mass equivalent to hundreds and thousands of suns.
7. THE FINITE SPEED OF LIGHT:
As you all know (especially Contemporary people), That the speed of
light is a finite value in a vacuum.
But when an object enters the event horizon of a black hole then it have
to move with speed more than light.
In order to gain speed more than speed of light infinite amount of force
is needed.
In all this universe there is no source of infinite force.
Therefore, the fallen objects never return.
12. FACTS ABOUT BLACK HOLES:
The massive gravitational influence of a black hole bends space time in the
near neighborhood.
The closer you get to a black hole, the slower time runs.
Material that gets too close to a black hole gets sucked in and can never
escape.
Black holes do not emit radiation on their own.
They are detected by the radiation given off as material is heated in the
accretion disk.
Their detection is also possible by the black hole’s gravitational effect on
other nearby objects or light passing by.
13. THE MILKY WAY GALAXY:
The Milky Way Galaxy is our home galaxy in the universe.
The Milky Way began forming around 12 billion years ago and is part of a group of about 50
galaxies called the Local Group which itself is part of a larger gathering of galaxies called the
Virgo Super cluster of galaxies.
The Milky Way moves through space at a velocity of about 552 kilometers per second.
100-400 billion stars are present in this galaxy.
Its galactic center is located about 26,000 light-years from Earth.
At the center of Milky Way Galaxy lies a super massive black hole named as Sagittarius A*.
This black hole contains the mass of about 4.3 million suns.
The Milky Way contains a few hundred million stellar black holes.
The speed of stars, gases and dust in accretion disk of this black hole is 220 kilometers per
second.
14. MILKY WAY CENTER: VISIBLE LIGHT VIEW:
The heart of our galaxy is a veritable soup of stars, gas, and
dust. On a clear night in a dark sky, the view is breathtaking.
15. MILKY WAY CENTER: X-RAY LIGHT VIEW:
Lurking within our galaxy’s hot, turbulent center are x-ray
binaries, neutron stars, and even a supermassive black hole.
17. FORMATION AND GROWTH OF BLACK HOLES:
When a star of mass more than 3 times
mass of the sun reaches to an end of its
life, it gets crushed in its own gravity
leaving behind a compact black hole.
Once a black hole has formed, it can
continue to grow by absorbing additional
matter like gases and dust from
surrounding to become heavier and larger.
Large black holes are formed by the
combination of small black holes and also
when small black holes absorb huge stars.
18. STEPHENS WILLIAM HAWKING’S THEORY:
Stephen Hawking’s great discovery
was that the mysterious regions in
space we call black holes radiate
heat.
Hawking said that these holes glow
like a hot body and smaller they are,
the more they glow.
Stephen Hawking’s theory says that
the temperature of a black hole
varies inversely to its mass.
19. RADIO JETS FROM BLACK HOLES:
Many black holes emit jets which moves
nearly with the speed of light.
These jets are composed of electrons and
positrons.
Magnetic field around black holes expels
material and form these jets.
Interaction of jet materials with magnetic
field gives rise to Radio emission.
20. HOW DO WE FIND BLACK HOLES:
The X-rays are sent off into space and
when they strike the matter around the
black hole , it can be detected.
Binary X-ray sources are placed to find
strong black hole .
Another sign of the presence of a black
hole is random variation of emitted X-
rays. And gravitational lensing ,accretion
disks and gas jets .
21.
22. X-RAY BINARY: X-RAY LIGHT VIEW:
More dramatically, matter being pulled off the orbiting star, into
the accretion disk of the black hole, glows brightly in x-rays.
23. CONTROVERSY ABOUT BLACK HOLE:
“There is no escape from a black hole in
classical theory,” Hawking told Nature.
Quantum theory, however, “enables energy
and information to escape from a black hole”.
A full explanation of the process, the physicist
admits, would require a theory that
successfully merges gravity with the other
fundamental forces of nature.
But that is a goal that has eluded physicists for
nearly a century. “The correct treatment,”
Hawking says, “remains a mystery.”