Stephen William Hawking (8 January 1942 – 14 March 2018) was an English theoretical physicist, cosmologist, and author who was director of research at the Centre for Theoretical Cosmology at the University of Cambridge at the time of his death. He was the Lucasian Professor of Mathematics at the University of Cambridge between 1979 and 2009.
Hawking was born in Oxford into a family of doctors. He began his university education at University College, Oxford, in October 1959 at the age of 17, where he received a first-class BA (Hons.) degree in physics. He began his graduate work at Trinity Hall, Cambridge, in October 1962, where he obtained his PhD degree in applied mathematics and theoretical physics, specialising in general relativity and cosmology in March 1966. In 1963, Hawking was diagnosed with an early-onset slow-progressing form of motor neurone disease that gradually paralysed him over the decades. After the loss of his speech, he communicated through a speech-generating device initially through use of a handheld switch, and eventually by using a single cheek muscle.
Hawking's scientific works included a collaboration with Roger Penrose on gravitational singularity theorems in the framework of general relativity and the theoretical prediction that black holes emit radiation, often called Hawking radiation. Initially, Hawking radiation was controversial. By the late 1970s and following the publication of further research, the discovery was widely accepted as a significant breakthrough in theoretical physics. Hawking was the first to set out a theory of cosmology explained by a union of the general theory of relativity and quantum mechanics. He was a vigorous supporter of the many-worlds interpretation of quantum mechanics.Hawking achieved commercial success with several works of popular science in which he discussed his theories and cosmology in general. His book A Brief History of Time appeared on the Sunday Times bestseller list for a record-breaking 237 weeks. Hawking was a Fellow of the Royal Society, a lifetime member of the Pontifical Academy of Sciences, and a recipient of the Presidential Medal of Freedom, the highest civilian award in the United States. In 2002, Hawking was ranked number 25 in the BBC's poll of the 100 Greatest Britons. He died on 14 March 2018 at the age of 76, after living with motor neurone disease for more than 50 years.
Does this mean that everything, including us, will turn into photons/electromagnetic waves some day? Sounds fun! A universe of matter converted entirely to light!
I couldn't find any papers yet on this on scholar.google.com
Here are some good articles though...
When a Kerr black hole evaporates, what will the Kerr parameter do?
Stay constant at initial value?
Approach zero?
Approach unity?
Approach a target value somewhere between zero and unity?
Also, Nordström black holes in practice (with matter around) would have a strong tendency to attract...
The intense gravity near the event horizon causes complementary particles to pop into existence spontaneously. As local space-time is continuous through the EV, the same would be happening just inside the EV, only more so as the gravity field and gradient is greater. So near the singularity...
The Hawking radiation comes from a pair of complementary particles, an electron and a positron for example, coming into existence spontaneously near the event horizon as a result of the intense gravitational field. One particle gets captured by the Black Hole while the other escapes, taking a...
How can a particle created just outside the event horizon with no velocity (?) escape a black hole, never to return, when black holes gravity is so strong that they can pull matter away from stars many kilometers distant?
I just noticed that Stephen Hawking, who was born Jan 8, 1942 and would have been 80 today,
is featured in the Jan 8, 2022 Google Doodle. (Visit https://www.google.com/ to see.)
https://www.google.com/doodles/stephen-hawkings-80th-birthday
Hello,
So I was reading about Hawking radiation and I read a QFT interpretation of it. It went something like this:
A vacuum contains virtual particles (vacuum energy), which in qft can be described as waves that are out of phase and cancel each other out (matter and antimatter). I a black...
Theoretically could an observer in a black hole perceive hawking radiation escaping the black hole as a black hole within the black hole? Also if so maybe that black hole could produce a radiation similar to or related to hawking radiation (Making a strange entangled system for conservation of...
Hi,
I'm a Portuguese translator working on a documentary about black holes and there is a specific bit of dialogue between Stephen Hawking and his colleagues that I'm having a hard time translating. Basically, Hawking says: "So, it could be the F plus minus
term takes this away." Is this the...
Hawking and Hartle proposed a well-known model which postulated a sum over all possible histories considering all compact euclidean metrics to explain the origin of the universe (this is called the No Boundary model).
I was wondering whether there is any model or theory (related to cosmology)...
In this video How we know that Einstein's General Relativity can't be quite right - YouTube , Hossenfelder says: "The [Hawking] radiation is entirely random and does not carry any information..."
I have heard and read this from a number of other sources, and never understood. Completly random...
The Hawking-Hartle no boundary condition is well known. The authors considered a many worlds/histories model considering a sum over all compact euclidean metrics.
But are there any models or theories that consider a sum over all possible metrics or boundaries?
And finally, if all possible...
Hello,
I take the example of two observers :
- A distant observer
- A falling observer
For the distant observer, the formation of the horizon is not part of his future cone of light, we agree.
For the falling observer, the consensus says it is crossing the horizon.
First question: the...
Physicists Stephen W Hawking and James B Hartle 1 proposed that the universe, in its origins, had no boundary conditions both in space and time.
To do that, they proposed a sum over all compact euclidean compact metrics. I have heard that they only considered these metrics in order to simplify...
I am grateful for anyone for their time to answer this question.
Some theories predict black holes will evaporate and eventually disappear. From my limited understanding, Hawking's theory predicts that quantum effects near the event horizon of a black hole are responsible for blackbody...
In this book series George, a school kid meets a neighbor Eric, a scientist . He's surprised to find that Eric possesses a supercomputer which can actually actually teleport people to space.
The book explains astronomical concepts like the red shift, true vacuum and false vacuum for instance...
If we take the perspective that black holes thermalize (reach maximum entropy) in a very short time and then just sit there and grow in complexity, how do we interpret Hawking radiation in this picture? i.e. you can't just have the state of the black hole keep growing in complexity forever...
I got a phrase from a book that Stephen Hawking and his daughter Lucy Hawking published in 2011. The book is "George and the Big Bang" which is a science fiction book prepared for children.
I read a phrase on that book that interested me. It was:
"Perhaps there are many universes, each with...
Hi,
i have a question which i can't solve myself, as i am not a student of physics:
I have heard of the infinite space curvature which occurs when matter collapses into a black hole.
On the other hand i have heard, that a black hole radiates energy away.
Now i see a contradiction: When the...
[Moderator's note: New thread spun off from previous discussion due to more advanced subject matter being discussed.]
There is, in fact, a quite good argument that Hawking radiation cannot be derived by semiclassical theory.
It is the comparison with the scenario where the collapse stops some...
It is known theoretical prediction that Black Holes must emit radiation "... its temperature and surface gravity are proportional to its mass divided by its area" (Kip Thorne). This is applied to Event Horizon (rg).
But one can imagine inner Black Hole (e.g. inside r' < rg), it does not have...
Summary: As hawking radiation is based on quantum fluctuations, can they cancel out each other due to equal probabilities of a particle remaining in or drifting away?
I recently learned how hawking radiation actually works. It is based on quantum fluctuations which happen randomly in space...
I know that has been discussed elsewhere but never could find for a satisfying answer, so I try this here again.
Let us not take into account that an observer (an astronaut or a clock or just let us take both: an astronaut with a clock) falling into a black hole (BH) will be killed and torn...
At least three items around March 14:
new documents from Einstein
a coin commemorating Hawking
Pi-Day
https://todayinsci.com/3/3_14.htm
Albert Einstein was born on March 14, 1879.
Among various documents of Einstein (acquired by Hebrew University to update their collection of his documents...
Hello.
I'm trying to pin down something Stephen Hawking was referring to in his book, A Brief History of Time.
During the next few years I developed new mathematical techniques to remove this and other technical conditions from the theorems that proved that singularities must occur. The final...
Stephen Hawking theorized the creation of virtual particle pairs at the event horizon of a black hole, with one of the particles escaping the event horizon (Hawking Radiation) and the other particle falling into the black hole.
Sean Carroll states on page 272 of From Eternity to Here that "if...
Hawking Radiation says that an antiparticle and particle spontaneously appear and annihilate each other everywhere, but at the horizon, if the antiparticle appearing inside the horizon and the particle appears outside, then the antiparticle is sucked in and the particle is emitted outward...
Is the cosmic backround radiation incident on a black hole sufficient to make up for the energy lost through Hawking radiation?
And what if we include the average energy flux from discrete objects like galaxies, as seen in intergalactic space?
Well known scientist professor Stephen Hawking had predicted the possibility that genetic modification can give birth to superhumans that could destroy the rest of humanity. The essays, published in the Sunday Times, were written in preparation for a book that will be published on Tuesday. Read...
This paper seems to claim, that there is found powerful observational evidence for some anomalies in the CMB that seems to suggest a conformal cyclic cosmology and so called Hawking points.
As I understand it, it also claims, that these points, were present in the very early universe and that...
Very recently, Roger Penrose, along with Daniel An and Krzystztof Meissner, have submitted a new paper to PRL. In the new paper they present new empirical findings which support CCC. It doesn't seem to be out yet though, I can't find it anywhere, but I will place the link here when it is out...
The following from Wiki re Hawking Radiation:“... vacuum fluctuations cause a particle–antiparticle pair to appear close to the event horizon of a black hole. One of the pair falls into the black hole while the other escapes. In order to preserve total energy, the particle that fell into the...
we say everytime a couple of matter-antimatter particles get born near the edge of a black hole one of them falls into it and the other one escapes.
And we everytime mention that the antimatter particle kind of eats a bit of black holes mass out...and by time the black hole gets smaller and...
Hawking and Hertog's new paper "A Smooth Exit from Eternal Inflation?" does away with the infinite multiverse of Hawking's previous theory and proposes a cosmology that predicts "a simpler and finite universe".
But I can't figure out the extent of this reduction to a "simpler and finite"...
The next questions will be in english and spanish, since my birth language is spanish I may be mistaken in a few english words.
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Spanish
Debo advertir que...
I have been considering Hawkin radiation and I am puzzled about the capture of a virtual photon. Given that the escaped photon is entangled with the captured photon I do not see how the escaped photon can shed the entanglement. Can anyone help with this?
I was discussing this with my class just the other day and now the sad news has come out, I was wondering where everybody thinks Hawking stands and where he will stand in 100 or even 200 years?
Will he be as widely known as Newton, Maxwell, and Einstein? Will his research and discoveries be as...
On Pi day and the anniversary of Albert Einstein's birthday, a great man, mathematician and scientist passed away.
Vale Stephen Hawking.
https://edition.cnn.com/2018/03/14/health/stephen-hawking-dead/index.html
Matter with negative mass, herein called “negative matter”, is different from antimatter.
P.A.M. Dirac, on theoretical grounds, proposed the existence of antimatter, and its
existence was later confirmed by experiment. Antimatter is the opposite of ordinary
matter in some ways, but just as...
A photon and a graviton are both certainly devoid of mass and charge.
Therefore a massive black hole can certainly Hawking radiate either.
Is the intensity of photon radiation and graviton radiation by a black hole exactly equal, or different at some specific proportion due to different...
Dear all,
I'm trying to understand the firewall controversy and the role of Hawking radiation in this. To make things concrete, I'll use the desciption of the firewall controversy of John Preskill here...
Hawking radiation formula shows the fact that when charge and angular momentum increases in a Kerr-Newman black hole (angular momentum in Kerr black hole) Hawking radiation decreases.
Can someone explain this?
Thank you.
first question
From what i read Hawking radiation is a particle and ant particle created on the event horizon of a black hole, one particle is pulled into the black hole letting the other escape, why does the one outside of the event horizon escape instead of both being pulled in? It would still...
Hi, I'm trying to understand the QM, I have no background and I can only do some research sometime because I've no time for this. Yesterday I read the quote above. He's talking about black holes and the horizon of events. I read that the microcosm can make indeterminate the macrocosm, for...
Are there kinds of black hole radiation other than that proposed by Hawking? Note that I'm talking about truly black hole radiation, not radiation from matter that orbits the black hole, etc.
How can we conciliate such phenomenon with General Relativity? I mean, this seems to completely...
I have some questions regarding the temperature of empty space in a de Sitter universe or to say it better - the Hawking radiation emmited from the cosmological horizon:
1) Do particles that make up the radiation get produced by the empty space inside the patch (the Bunch Davies vacuum) or by...