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what would happen if you took the most
energetic light source in the universe
and smashed it into a massive
gravitational monster
well you might reverse the flow of time
how would this event unfold
how could it affect time as we know it
and
what would happen if you got too close
this is what if and here's what would
happen if a gamma ray burst hit a black
hole
meet your first fighter a black hole
not so different than your average
object with mass
except that it's extremely
dense
most black holes are the remnants of
massive stars
and they have lots of gravity
the mass of this black hole is
compressed to a point called a
singularity
at this infinitely small point in the
center conceptions of space and time
break down today's challenger is a gamma
ray burst
not so different from your average burst
of visible light
oh yeah except way more energetic
gamma ray bursts are the strongest and
brightest explosions in the universe
in one second gamma ray bursts emit as
much energy as the sun will emit during
its entire 10 billion year life span
so if these two powerful phenomena
collide
would space and time cease to exist
no matter what happens next in this
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yeah 20 off at g-r-a-m-m-a-r-l-y
dot com slash what if
with these two monster forces coming at
each other
i have only one message for you right
now
duck
there are a couple of things you should
know before we get underway with our
space-time obliterating cage match
the first is that our two contenders
already interact pretty often
a black hole releases a burst of
gamma-ray light when it's created
this burst spreads out evenly in all
directions across the universe
so some of these gamma-rays will
certainly encounter another black hole
or two
and these gamma-ray bursts happen about
once a day
they could flash for less than two
seconds or
they could last for up to 30 seconds
the difference is whether the burst
results from two neutron stars colliding
to form a black hole or
whether it's the result of a star
collapsing directly into a black hole
without a supernova explosion
so
if you managed to observe these
phenomena
would you witness a magnificent
explosion about a million trillion times
brighter than the sun
well not quite
while some photons have just the right
amount of frequency to be visible to
your eyes
the frequency of gamma rays is way too
high your eyes aren't advanced enough to
see their beautiful bursts
but if you could see them this insane
amount of light would probably leave you
blind
now surely this explosion must be loud
right
well once again i come bearing bad news
it would technically
sound like nothing
yeah
sound doesn't travel in the vacuum of
space
it needs a medium with particles to
carry sound waves
but thanks to the scientists at nasa
a gamma ray burst would sound a little
something like this
okay not exactly like this
these beautiful cello and piano notes
translate the gamma-ray frequencies into
musical notes
pretty mellow for such a massive
explosion right
but if you were close to this explosion
things would be
anything but mellow for you
gamma rays are hazardous
they can penetrate lead concrete and
certainly whatever space suit you'd be
wearing
as they passed through your body they'd
deliver an extremely high dosage of
radiation
you'd suffer radiation sickness you'd
become nauseous
lose your hair and even bleed
the energy could cause damage to your
tissue and your dna
leading to cancer or
worse
death the gamma rays could cook you from
the inside out
so
you'd want to back up a little bit
or better yet reverse time
in 2018 researchers observing gamma-ray
burst pulses found that some events
repeated themselves in reverse
that's right it was as if they were
moving backward
so
what does this mean for you
did you just stumble on a way to travel
back in time
again i have bad news
this is merely an optical phenomenon
light has the fastest speed in the
universe but this is only true for the
speed of light traveling through empty
space
in other mediums like water
it would be possible for electrons to
travel faster
that means if gamma rays could travel
faster than the speed of light
they would give the illusion of
reversing time
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so yeah it's possible i oversold you a
bit on the idea that if a gamma ray
burst collided with a black hole it
would result in the brightest loudest
time destroying explosion of all time
but in some ways it's all true
now until our sun collapses into a black
hole and sends a burst of gamma rays in
your direction
you don't have to worry
but
if a black hole swallowed our sun
gamma rays wouldn't be your only problem
but that's a story
for another
what if
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you