00:00:00
hello un person this is Anton and in
00:00:02
this video we're going to discuss humble
00:00:04
attention and the discoveries in regards
00:00:06
to the mysterious Dark Energy once again
00:00:09
or essentially the idea that something
00:00:11
about the expansion of the universe
00:00:13
currently does not make a lot of sense
00:00:16
and so let's talk about some of the most
00:00:17
recent discoveries and some of the most
00:00:19
recent confirmations but let's actually
00:00:22
get some of the history out of the way
00:00:24
first just so that there's no confusion
00:00:26
about what we're discussing and what
00:00:28
these Concepts actually we mean and here
00:00:30
the story starts sometimes in the late
00:00:33
1990s specifically around 1998 during
00:00:37
this time three scientists Soul perter
00:00:40
Adam Reese and Brian Schmidt used type 1
00:00:43
is Supernova to accidentally discover
00:00:45
something an usual about the universe
00:00:47
this was part of the Supernova cosmology
00:00:49
project and it essentially confirmed
00:00:51
that for some reason the universe is not
00:00:53
just expanding which is something we've
00:00:55
known for several decades by that point
00:00:57
but for some reason that expansion is is
00:01:00
also actually increasing or accelerating
00:01:03
implying that the farther away from
00:01:05
Earth you go the more the universe seems
00:01:07
to expand away from us with that
00:01:09
expansion accelerating over larger and
00:01:11
larger distances and because there was
00:01:13
no way to explain any of this back then
00:01:16
or I guess even today it became known as
00:01:18
dark energy some kind of a very bizarre
00:01:21
energy that seems to be causing the
00:01:22
expansion to accelerate more and more
00:01:25
and that also seems to represent the
00:01:27
majority of energy in the entire
00:01:29
universe if it represents approximately
00:01:31
72% of everything that the Universe
00:01:33
contains and because this was such a
00:01:35
groundbreaking discovery in 2011 they
00:01:38
were awarded the Nobel priz in physics
00:01:40
and back then they discovered this value
00:01:42
of acceleration to be approximately 72
00:01:45
km per second per Mega parac or
00:01:48
essentially for every 3.2 million light
00:01:50
years that you cross the expansion of
00:01:52
the universe increases by 72 km/s with
00:01:55
the uncertainty being approximately 10%
00:01:58
but ever since at Nobel price since 2011
00:02:01
things actually got a little bit more
00:02:03
complicated because additional
00:02:05
observations from various surveys and
00:02:07
from various telescopes started to
00:02:08
uncover something else bizarre bizarre
00:02:10
in a way that some of the measurements
00:02:13
especially using different methods were
00:02:15
not actually getting the same results
00:02:17
now in some cases this was due to
00:02:18
uncertainty or due to the error bar but
00:02:21
in some cases it was not and here let's
00:02:24
actually briefly talk about how some of
00:02:26
this is measured just so that you
00:02:28
understand what the problem is so in
00:02:29
cons ology in order to measure this
00:02:31
expansion and the acceleration of the
00:02:33
expansion we first have to figure out
00:02:35
how to even measure distances and to
00:02:38
solve this bizarre problem over decades
00:02:40
researchers developed a lot of really
00:02:42
brilliant techniques this is known as
00:02:44
the cosmic ladder where every single
00:02:46
rung of the ladder essentially
00:02:48
represents some kind of a distant object
00:02:49
that we're familiar with where the
00:02:51
distance is well known and then by
00:02:53
comparing distance between this object
00:02:55
and something else we can basically
00:02:57
start making certain conclusions about
00:02:59
the universe and its expansion and for
00:03:01
some of the nearby galaxies and nearby
00:03:03
objects there's actually a really famous
00:03:05
type of stars that's always been used
00:03:07
for this they're known as safid
00:03:10
variables one of the most famous safid
00:03:12
variables is actually the one located in
00:03:14
the Andromeda galaxy and it's the one
00:03:16
that back in the days in 1923 I think
00:03:19
Edwin Hubble discovered by accident and
00:03:21
realized that it was actually really far
00:03:23
away from us thus realizing that
00:03:25
Andromeda was super far away and that
00:03:28
the Milky Way galaxy was not the only
00:03:29
Galaxy out there essentially by using
00:03:32
this sa variable he discovered the
00:03:34
entire universe now we're going to be
00:03:36
talking about this star in a little bit
00:03:37
more detail in a separate video so do
00:03:39
subscribe if you want to learn more but
00:03:41
in essence these unusual stars produce
00:03:43
very specific and predictable pulsations
00:03:46
when they get brighter they pulsate more
00:03:48
slowly and that enables astronomers to
00:03:50
measure their fundamental intrinsic
00:03:53
brightness and so by comparing this
00:03:55
brightness to what we know about SE
00:03:56
variables around us we can create a kind
00:03:59
of a c distance L by using just sa
00:04:02
variables allowing us to measure
00:04:04
distances to some the nearby galaxies
00:04:06
and even galaxies millions of light
00:04:08
years away from us then apart from
00:04:10
separate variables we can also use the
00:04:12
brightness of type 1 a supernova
00:04:14
exploring wi wors that usually produce
00:04:16
relatively similar brightness as well
00:04:18
mostly because they all explode at
00:04:20
around the same mass 1.4 solar masses
00:04:23
and so here by using combination of
00:04:25
sapid variables exploring wide worth and
00:04:28
a few other pulsating Stars over the
00:04:30
years researchers worked out different
00:04:31
values for the cosmological constant or
00:04:34
for the expansion of the universe with
00:04:36
most values usually being around the
00:04:38
same number 72 in some cases a little
00:04:41
bit less in some cases a little bit more
00:04:43
but one of the major problems with most
00:04:45
of these studies has always been lack of
00:04:47
samples or maybe slightly different
00:04:49
analysis techniques and so back in 2019
00:04:52
by using the h space telescope
00:04:54
researchers were able to confirm a lot
00:04:56
of these observations establishing this
00:04:58
latter extremely accurately but to
00:05:01
confirm this once again this was done
00:05:02
just a few months ago with the James web
00:05:04
with both telescopes using slightly
00:05:06
different techniques now essentially
00:05:08
confirming that all of the previous
00:05:10
calculations were relatively correct and
00:05:12
because both telescopes in this case
00:05:14
used different measurements as in they
00:05:16
actually use different wavelengths of
00:05:17
light gwst was using infrared and hub
00:05:20
telescope was using optical light having
00:05:23
these two results match one another was
00:05:25
a really important First Step It
00:05:27
basically validated many different paper
00:05:29
from the last decade and suggested that
00:05:31
the values for the Hubble constant for
00:05:33
many of these studies was very likely
00:05:36
correct which was a bit of a problem
00:05:39
because now let's take a look at the
00:05:40
other way of measuring this that was
00:05:42
actually done a long time ago and has
00:05:44
been confirmed several times by using
00:05:46
entirely different telescopes and a very
00:05:48
different analysis and this was the
00:05:50
analysis based on the earliest light in
00:05:52
the universe the CMB or the cosmic
00:05:54
microwave background and actually
00:05:57
another method known as B oscillations
00:05:59
which I've discussed in one of the
00:06:00
previous videos in the description that
00:06:02
essentially uses what's known as the
00:06:04
ancient relics to try to estimate the
00:06:06
expansion once again but here basically
00:06:08
focusing on the early Universe from
00:06:10
billions of years ago and the thing is
00:06:12
because the observations of the CNB are
00:06:14
so extremely accurate here the error is
00:06:17
only 1% but every single study that used
00:06:20
this light to try to calculate how fast
00:06:22
the universe was expanding approximately
00:06:24
13.8 billion years ago discovered the
00:06:27
same value and the value was much much
00:06:30
lower closer to about 67.4 km/s per Mega
00:06:34
Parc with an extremely small error
00:06:37
completely incompatible with previous
00:06:39
discoveries of 72 km/s and basically
00:06:42
very different from every other
00:06:43
observation conducted in the last decade
00:06:46
and so essentially here we had the early
00:06:47
observations and the late observations
00:06:50
and they did not match and that's in
00:06:52
essence the Hubble tension something the
00:06:55
researchers have been trying to resolve
00:06:57
for the past decade or so and something
00:06:59
that still does not have resolutions
00:07:01
with some of the recent studies actually
00:07:02
now claiming that this is no longer
00:07:04
attention this is now an official crisis
00:07:08
a crisis because it's now been also
00:07:10
confirmed by some of the most detailed
00:07:12
additional observations including the
00:07:14
famous dassi Dark Energy spectroscopic
00:07:17
instrument the instrument that was
00:07:19
specifically designed to study Hubble
00:07:21
attension and to resolve these issues
00:07:23
and here was doing this by observing
00:07:25
approximately 100,000 different galaxies
00:07:28
and using their spectroscopy to
00:07:29
determine exact distances by using the
00:07:32
kit Pig national Observatory and some of
00:07:34
the most recent observations from Desi
00:07:36
from just a few months ago definitively
00:07:38
confirm the universe is expanding faster
00:07:41
than predicted theoretical models and
00:07:43
even faster than current physical models
00:07:45
can explain basically confirming the
00:07:47
Hubble tension is a crisis and it seems
00:07:50
to be real now this particular study
00:07:52
we've discussed in more detail in one of
00:07:54
the videos in the description but now we
00:07:56
have another study that used a
00:07:57
completely different technique TR to
00:07:59
basically come up with a way to study
00:08:01
all of this by using some kind of an
00:08:03
independent Cosmic layer and by trying
00:08:05
to calculate their own value for the
00:08:07
Hubble constant without using any biased
00:08:09
data and so in this study Daniel Schick
00:08:12
and his team combined the observations
00:08:14
from Desi with essentially what we know
00:08:16
about the famous coma cluster a very
00:08:19
well-known Galactic cluster basically in
00:08:21
our own backyard whose distances have
00:08:23
been measured many times before but in
00:08:25
this case they wanted to do this again
00:08:27
using their own data in order to then
00:08:29
try to calculate the hble constant
00:08:32
completely independently so essentially
00:08:34
here they focused on creating a kind of
00:08:36
a first Rong in the cosmic lad and so by
00:08:39
anchoring this lad in a much more
00:08:41
accurate data it would become possible
00:08:43
to work out if there is a Hubble tension
00:08:45
after all but to get the most precise
00:08:47
distance to this cluster researchers had
00:08:49
to once again rely on type 1A Supernova
00:08:52
luckily for them they found 12 12 tiny
00:08:55
candles in a distant Galactic cluster
00:08:58
that allow them to work out their own
00:08:59
independent distance and here it was
00:09:02
calculated to be approximately 320
00:09:04
million light years which is actually
00:09:06
right in the middle of previous
00:09:07
measurements and extremely close to a
00:09:09
lot of other measurements conducted in
00:09:11
the last decade and that basically
00:09:13
created that first candle and so by
00:09:15
using this first measurement they were
00:09:17
able to work out what the Hubble
00:09:19
constant should be in this location as
00:09:20
well by basically observing how much
00:09:22
those Supernova were receding away from
00:09:25
us or by how much SpaceTime has
00:09:27
accelerated at these extreme distances
00:09:29
and they came to a value of
00:09:31
approximately
00:09:32
76.5 km/s per Mega Parc and that's
00:09:36
because at this distance these Supernova
00:09:38
were moving away from us at
00:09:39
approximately 7600 km/s due to the
00:09:42
expansion but because their values had
00:09:44
an air of plusus 2.2 km/s it did
00:09:48
actually match some of the previous
00:09:50
observations that use safid variables
00:09:52
and Supernova before but it was way way
00:09:55
above the measurements from the CMB in
00:09:57
essence once again confirming the H
00:10:00
tension seems to still exist even when
00:10:02
you conduct completely independent
00:10:04
measurements with all this confirmed
00:10:06
even further when Adam Ree and his team
00:10:08
used new data from jwst to double and
00:10:11
even triple check certain observations
00:10:13
of saf variables and type one Supernova
00:10:16
which also resulted in somewhat similar
00:10:19
values very different from the values
00:10:21
seen in the early universe and so time
00:10:23
and time again pretty much every study
00:10:25
so far produced the same conclusion the
00:10:28
hension is is now basically some kind of
00:10:30
a crisis and it does not have a very
00:10:32
good explanation but there might be some
00:10:34
explanations for example maybe there is
00:10:37
actually some kind of a systematic error
00:10:39
either error in the early Universe
00:10:41
observations or the error in late
00:10:43
Universe observations that were just not
00:10:45
noticing and everyone's making the same
00:10:47
mistake what exactly this error would be
00:10:49
is obviously currently unknown but
00:10:51
because here different instruments have
00:10:53
been used to measure this whatever it is
00:10:55
you would have to affect many different
00:10:57
instruments in many different to SCH
00:10:59
goes so right now the error explanation
00:11:01
is really not that popular or maybe
00:11:04
there is some kind of a still unknown
00:11:06
effect in the entire universe that's
00:11:08
basically causing the hubo constant to
00:11:10
not be a constant and to change over
00:11:13
time which if true would cause a lot of
00:11:15
other troubles for cosmology because a
00:11:17
lot of calculations kind of depend on
00:11:19
the H constant to be a constant so yeah
00:11:22
if that's true then things will have to
00:11:25
be reworked for many many years likewise
00:11:27
maybe there is just some kind of new
00:11:29
physics something completely unknown
00:11:31
inside the cosmological model and
00:11:33
something that cannot explain everything
00:11:35
just yet maybe a different model such as
00:11:38
the somewhat Infamous mon or the
00:11:40
modified Newtonian Dynamics could
00:11:42
provide better interpretation but the
00:11:44
problem with mon as we've discussed in
00:11:45
some of the previous videos is that
00:11:47
right now it has a crisis of its own a
00:11:49
lot of previous observations basically
00:11:51
almost definitively show that it might
00:11:53
not be correct there are some videos in
00:11:55
the description that talk about this
00:11:57
more or maybe there's some other really
00:11:59
bizarre explanation such as the recently
00:12:01
discussed Timescape model so that's the
00:12:04
model where instead of imagining
00:12:05
universe as kind of flat and similar
00:12:08
everywhere some scientists try to
00:12:09
explain it as basically having these
00:12:11
unusual time dilation regions where time
00:12:14
just flows differently depending on the
00:12:16
mass now that model we discussed
00:12:18
recently as well once again right there
00:12:20
but those observations only really make
00:12:22
sense for some of the universe near us
00:12:25
if you look at the Grand scale of things
00:12:27
even the time skape model would not
00:12:28
really explain everything and I think
00:12:30
PBS eons actually produced a video about
00:12:32
this with the link in the description
00:12:34
which in essence explains why the
00:12:36
Timescape model might also not be a good
00:12:39
answer but the conclusion is that over
00:12:41
the years and pretty much every single
00:12:42
month now we get new details we get new
00:12:45
papers new studies that keep discovering
00:12:47
the same the tension is real the tension
00:12:50
is now a crisis and it doesn't really
00:12:52
have a good explanation because the
00:12:54
observations from Desa right now reveal
00:12:56
that the Universe seems to be evolving
00:12:58
over time with dark energy potentially
00:13:01
changing in a process the only way this
00:13:03
could be resolved is by having even more
00:13:05
observations and even more data from a
00:13:08
lot of different regions of the universe
00:13:10
and so once Desi completes its Mission
00:13:12
and produces basically the largest
00:13:15
threedimensional map of the entire
00:13:16
universe ever we might finally start
00:13:18
making sense of all of this and maybe
00:13:20
finally figure out what's going on here
00:13:22
but until then that's basically where
00:13:25
I'm going to leave you there's no answer
00:13:27
this is still a big mystery possibly
00:13:29
even more mysterious than a few years
00:13:31
back and nobody has any solutions to any
00:13:33
of this just yet but once we have some
00:13:35
solutions or some new propositions we'll
00:13:37
come back and discuss this in some of
00:13:39
the future videos until then thank you
00:13:41
for watching subscribe share this with
00:13:42
someone who loves about space and
00:13:43
Sciences come back tomorrow to learn
00:13:45
something else support this channel
00:13:46
patreon by joing Channel membership or
00:13:48
by buying the wonderful person t-shirt
00:13:50
you can find in the description stay
00:13:51
wonderful I'll see you tomorrow and as
00:13:53
always bye-bye
00:14:03
[Music]
00:14:12
[Music]
00:14:29
e
