Stephen Hawking’s scientific contributions and science heritage @BreakthrouhScience


hi and welcome to breakthrough science
Benjamin here! Stephen Hawkins one of the greatest thinkers of our time died March
14 2018. This session is about Stephen Hawkins scientific heritage in short
about BIGBANG’s and black holes. Enjoy! Stephen Hawkins was diagnosed with ALS
amyotrophic lateral sclerosis this disease should have ended his life five
years after the diagnosis, nevertheless, now more than fifty years after this
diagnosis his life finally ended and he leaves back a great heritage of public
outreach scientific discoveries and a strong will to live! Okay let’s start
with a crash course in big bang science The universe started in a very small
little point all mass all energy was contained there until it began to expand,
accelerating outwards, forming a dust of atoms, colliding, getting heavier,
assembling until the first rocky bodies, which were the foundation for planets
and stars, came into existence. The whole universe with all the galaxies in it
keeps expanding up to this day. Nowadays the theory is widely accepted but it hasn’t been the case in the 1970s as Hawking developed together if Penrose,
the on general relativity based, idea that the universe began as a singularity.
Okay okay one moment let me try to explain the statement. Einstein’s general
relativity theory described gravitation as a property of the universe which is
altered by mass and can even be rippled and emit gravitational waves. In 2017
these waves were measured for the first time
Einstein furthermore predicted that an object can collapse under its own mass
transforming into a singularity. the gravitational pull of these
singularities is so strong that not even light can escape them. Does this sound
familiar a pull so strong not even light can escape? Yes, we are talking about a
black hole. So we might simplify Hawking’s and Penrose’s theory and say
that the Big Bang was like the collapsing of a black hole in reverse.
After that Hawking continued his research of black holes and argued that
black holes always increase and never decrease in size. In order to combine this
with thermodynamic laws he had to work on the holy grail of modern physics the
unification of the general relativity theory with the quantum theory. He didn’t
manage that but he found himself proofing that his original idea of black holes always getting heavier was wrong. Black holes can shrink after all and by doing so they might emit the now called Hawking’s radiation one other big discovery in Hawkings CV. Hawking radiation is based on a quantum mechanical principle that an empty space free of any atoms – Particles are continuously coming into existence. They appear in pairs of one matter and one antimatter and they
annihilate almost immediately. Hawkins argued that if this happens
close to a black hole one particle can be soaked in while the other one is
transferred into the universe. If the one who is soaked in is antimatter the total
energy and therefore the mass of the black hole decreases. That was another session of breakthrough science I hope you join me
for my regular video next week Wednesday and until then stay tuned stay curious
see you soon