Cosmic inflation: is it how the universe began? - with David Mulryne
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- Опубліковано 10 тра 2024
- What happened at the beginning of the universe, before the hot big bang? Join astronomer David Mulryne as he gives an introduction to cosmic inflation.
Watch the Q&A here: • Q&A: Cosmic inflation:...
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This lecture was recorded at the Ri on 13 July 2023.
For years, there has been a broad consensus in the cosmology community that the 'hot big bang' accurately describes the history of our universe since it was less than a few seconds old. But the question remains, what came before the hot big bang?
David Mulryne delves into the limitations of our current thinking and sheds light on the questions that remain unanswered. According to the hot big bang model, the Universe grew from a hot dense state, and ultimately in this model an 'initial singularity' from which time is measured. However, we only have direct evidence of what happened from when the Universe was a second or so old, and the events prior are still open to debate. Using the very latest findings and insights from the field of cosmology, David explores the leading ideas for what happened before this time, focusing on the theory of cosmic inflation as well as alternative ideas of the Universe’s origin.
David Mulryne is a Royal Society University Research Fellow in the Astronomy Unit, School of Physical and Chemical Sciences, Queen Mary University of London. After completing his MSci at Cambridge and PhD at the Astronomy Unit at Queen Mary, David held postdoctoral positions at DAMTP Cambrdige, the Theory Group Imperial, and at Queen Mary, before being awarded his research and proleptic fellowship in 2014. His particular area of expertise is cosmological inflation, a period of rapid expansion thought to occur before the hot big bang, however David also has extensive experience in teaching, outreach and public engagement. He has been a member of various national grant panels and is currently a member of the STFC Astronomy Grants Panel.
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For those , with some basic PS knowledge , skip to 36:09 . That`s where he gets on the topic of his lecture.
Kind of a bummer that I'm about to spend an hour watching this and I already know how it ends.
0:31: 🌌 The universe was different before the hot Big Bang model, with everything closer, hotter, and denser.
5:42: 🌌 The speaker discusses the special nature of our universe, the concept of inflation, and the size and structure of the universe.
11:34: 🌌 The universe was very smooth and even when it was young, with only small variations in temperature.
16:49: 📡 The law stating that galaxies that are twice as far away are moving twice as fast is a result of the smoothness and uniformity of the universe.
22:13: 🌌 The image is being stretched to show the expansion of the universe, with galaxies maintaining their relative positions.
27:21: 🌌 The universe is expanding, with everything getting further away from each other as space-time itself grows.
32:59: 🌌 The speaker wants to show the expansion of the universe in a more realistic way.
37:55: 🌌 The universe is smooth and homogeneous, with everyone experiencing the same expansion from the Big Bang explosion.
43:10: 🌌 The homogeneity problem addresses why the universe is so smooth and homogeneous everywhere.
48:15: 📈 Exponential growth is illustrated by taking something and multiplying it by a number greater than one, causing acceleration in growth.
53:14: 🌌 Inflation theory explains the homogeneity and horizon problems in the universe.
57:43: 💫 Quantum fluctuations in the field during inflation give rise to the structure and formation of galaxies in the universe.
1:02:35: 🔬 Inflation in the universe can lead to Quantum fluctuations and the creation of disconnected bubble universes with different physics.
Recap by Tammy AI
Just what time-starved folks like me need. Thank you Tammy AI!
Hot and smart 😍
Ai 🪄
It's amazing that we worked any of this out.
nothing is worked out, nothing he's said has any proof actually, they are just spit balling and guessing and pretending its real science.
Thousands and thousands of super smart peeps dedicating their minds and lives to the question of nature mathematics and methodology. Finally we get close enough to the truth to know, THERE IS SO MUCH MORE TO LEARN. And it takes a huge human sized effort.
We probably won't know "the lot" until we are all free to pursue pure thought endeavours.
Not Celestine Prophecy, but something close to that. Open minded people, interested in the truth, unhindered by CRAPOLA. Focusing together on The Work.
Lovely presentation. Thank you.
15:40 the way the whole universe is summed is beautiful to watch.
We felt very small in this comparison 😂
This presentation is mis-titled. It should have been called, "An Introductory Overview of Cosmology and the Big Bang". The speaker doesn't really start talking about inflation theory until the last ~10 minutes of the talk and simply lists some of the various models rather than discussing them. It's a nice talk, but it's an introductory presentation of cosmology for a lay audience, not a discussion about the merits of, and issues with, inflation theory.
Clickbait
Yes very basic, I still listened but kind of a waste of time
Thanks for the info. I was waiting for some deep understanding of inflation.
THEY ARE JUST NOT SURE ABOUT ANYTHING TO TALK IN DETAIL. ITS ALL HYPOTHESIS AT BEST & PLAIN GUESSWORK TO THE LEAST⚛️
The famous desk looks great! Glad to see it's back home.
Thank you. This was an excellent talk by a gifted explainer.
The bucket of sand analogy always works well, what really does hit home though and how I explain the scale is by adding the fact that between each grain of sand is ~4 light years, and would take the fastest thing we have made, 73,000 years to make 1 single hope to the nearest star!! That's when you start to realise space is big, very big!" ;-)
What illustrates it even more impressively is that when you picture our nearest neighbor star and the Sun as two specks of sand, then Alpha Centauri would be located on a beach approximately 15 miles away.
Thanks for making this video. I have no clue what I just listened to. Lost it at the growth of inhomogeneity.
This is such an awesome presentation on what we know about the ultimate “origin story” = the Big Bang!
Sup BK?
None can *Know* anything of the past, given that to know is to directly immediately personally experience, as directly immediately and personally as pain. which obviously cannot be collective so no we know, and fortunately no we hurt or experience pain or we experience anything, there being no we.
But you *Don't* know Anything, do you? You are merely the dustbin in towhich witless wiseacres tip thewiseacreings as if you were a midden.
When and *Only* when we has a headache can "We"know. it is rthe hallmark of the halfwit that he uses " we" know"
we can no more know than we can have a headache -or -If only you would, jump from the top of the nearest tall building
this man is wonderful. incredible.
why don't you that suppose him to be wonderful believe him? However the better question is why believe anything you are told. I suddenly recall that you savages sometimes use incredible which means not believable to mean jolly god but being savages you cannot help it you poor creatures that like parrots can reproduce words but have no idea what they mean.
0:52 “ Everything in the universe is getting further and further away from everything else”.
On a more human scale my socket set is absolute proof of this.
He said when you zoom in on anything it becomes smoother. I remember my math teacher showing us this with Integration and how you zoom in on a curved line and it becomes more straight. But this is not always the case. There can be what looks like a straight line from a distance but when you zoom in you see it is a high frequency sine wave or some other jiggling function. The Mandelbrot function never becomes a smooth line. Zn+1 = Zn2 + C . Then I thought of a circle. 2πr If you look up the definition of a circle , it has a center point and a radius and the circle is defined as all the points that distance from the center. But in the real world you have quantum fluctuations and the center of any circle is moving around and vibrating. The radius is also not a fixed distance because of the uncertainty principle. So now if you make a circle with these things in mind , and you zoom in on the circle line, you will see it as very wiggly and the distance around this circle will not be 2πr It will be higher. 2πr is the distance around a circle in a classical world where planks constant is zero. Which is obviously wrong. To get the actual distance of the circumference of a circle you have to use QM and do what Feynman did and add up every possible circle there could be and average out the circumference. The same things goes for addition like 1+1. You need to add up all the possible ways you could every add 1+1 together. If will be higher than the classical 2.
In which contexts are which we referring to? Universe or the market?
Thanks! I knew all of the concepts but now the relationship between them has become much clearer! :)
@toxyl3915 __ Could you help me to explain it to my brother in a few simple sentences? My brother Mark has an IQ of about 73 (he's working on improving it by watching science videos and has cut down a lot on his fluids) and he loves Star Trek, Dr Who, and all this other science stuff, but he's really struggling with this video. Half the problem is the nervous and shifty presenter, but I'm also having a tough time helping my brother to understand because I also don't understand it. Since you already know all the concepts, perhaps you could explain it in very simple terms? Thanks in advance.
@@SpongeBobImagination that's a task a that goes beyond the scope of a youtube comment. but let's take, for the sake of example, the CMB (cosmic microwave background). it's a 2-dimensional image (only has width and height, no depth). it is often referred to but its relation to how our universe looks today is not perse clear.
the link he puts there is that this is not just 2D, but can be seen like bubbles that expand over time:
think of each dot in that image as a bubble that grows in all directions. it pushes everything further away as it grows. that makes the entire structure grow. because of very small differences these bubble do not grow at the same rate and also start pushing at each other. the differences are the color differences in the image. even the biggest difference in color is still a small change in temperature (that's what the CMB image shows) though.
when you keep going on expanding these bubbles you get vast areas of "empty" space and a few places where the bubbles touch. these are the places where galaxies and stars are born.
additions and corrections to this explanation are welcome!
@@SpongeBobImaginationhi, Astrophyisics major here.
I'm sure i'm not in the minority to say that, even for us, these subjects isn't formally taught up until, two years in, that said, simplifications might not do the concepts justice, and may lead to misinformation/misconceptions altogether.
However, i'd try my level best to communicate it, do take it as trivial fun facts and nothing more though, and don't feel bad that you can't grasp everything completely, many of the informed technical words required basic understanding and or definition, as in dimension, vectors, ... such is cosmology.
Is it possible to have a big bang in middle of university to see what would happen.
The Inflation part starts at 45 minutes.
He is a very good speaker. I find the mix of advanced topics and basic ones to be puzzling. He almost assumes that you are familiar with non-Euclidean geometries and Heisenberg's
Uncertainty Principle but sketches out in a very basic way. I kept thinking yes yes but please get on with it and give the topic some depth
The hypothesis of inflation seems artificially forced in to salvage a theory of the early universe that just doesn't work. Sir Roger Penrose's hypothesis make a lot more sense.
25:50
You could pick up three points in the space energy diagram and measure their angle, if they add up to 180 universe is flat, if they are more than 180° it is elliptical and if it is less than 180° it is spherical.
Uh intersting isn't it.
This idea I got from here.
Hope I could work on this in future.
Thanks 😊 Royal Institution and happy 225th birthday
I'm still not convinced by the inflationary theorists but this is by far the best explanation of it I've seen anyone make so far - including Guth!
The good thing is you dont have to be convinced.
Thanks!
Thanks for another great video, look forward to many more!
I mean this with no sarcasm or hate: what an interesting accent. At times you sounded like you were from Northern Ireland, but at others almost RP or very upper class London, and it mixes in such an interesting way.
Interesting is the cycling cosmos. My biggest concern is...
Does each universe collapse into its own distinct bounce-out, or do all the universes in the "current" Cosmos collapse in together at some point/place/time?
I can see an exponentially growing parameter space of COSMII in a scenario where every single U goes on to create a multitude of progeny. Who then go on to repeat the action.
It's unlikely that anything ever collapses. Eternal inflation sounds like the far better concept.
this is all so unbelievibly real....
Construction of telescope send as to see galactic where matter is concentrating and other we must imagine.
Question if everything is expanding away from us. Please explain why the galaxy Andromeda will be joining our galaxy in the future to provide us with new places and stars to explore?
According to my understanding, Andromeda and Milky Way is "gravitationally bound". But I might be completely off. It's just a hobby for me to be honest.
@@saumalyasarkar7685 we are not going to be left alone in the universe for a very long time is my point. What you said had been said and other galaxies are also involved in the same attraction.
So, when 2 galaxies love each other very much, they come together to create 1 big galaxy. They vow to stay together until the heat death of the universe do them apart 😁
On a serious note, it's a misconception that the expansion of the universe is pulling EVERYTHING apart. That's happening only on massive distances. In shorter distances, such as between galaxy clusters, gravity wins keeping everything together.
However, if the rate of expansion keeps increasing, then there will be a time in the distant future where galaxy clusters will be pulled apart. Then even more in the distancer future galaxies themselves will get ripped apart... Then solar systems... Then planets... Cosmologist don't know for sure if it's gonna happen. They think that the heat death is a more likely outcome. Anyways, they call it "the big rip". You can look it up on UA-cam.
@@Mr.Anders0n_ attraction by gravity would possibly romantically be concerned love but GOD knows we can always use new resources.
Still confused about how we didn't just end up with a universe of just black holes from all the matter being so compressed in the early moments.
From what I know isn't that down to quantum fluctuations meaning matter wasn't evenly distributed?
Ok, think of our solar system. Why do we have planets? Why didn't the gravity of the sun gobble up the entire dust cloud? Because there are many things at the play: how evenly the dust is distributed; phenomena other than gravity such centrifugal force, outer radiation pressure, etc.
@@Mr.Anders0n_ Our, or any other, solar system is not equivalent to the density/pressure of the early pre-inflation universe, which is the timeframe I'm unclear about. I presume there is some hand-wavy explanation around how inflation makes it work out, but I'm hoping for clarity on that.
Expansion was reaaaaaaly fast in the beginning. Things moved away from each other too fast to attract and form a BH.
the acceleration of expansion was greater than the acceleration of gravity so expansion won for a few billion years
terimakasih
The ads are so loud that pop in
Speaker misspoke by saying 400 billion stars in our observable universe. When it should be 400 billion galaxies
Verbose to the point where it is harmful, meaning that the concepts would have been much easier to understand if he'd use fewer words.
From India:
The Vedas - is supposed to - describe the condition - before the time of creation - of the universe. 'They have been shaped - in the form of books.'
'What existed then ? The same churning condition and the creation of the atom.'
From: Ram Chandra. Vibration, sound and symbol. Complete Works, v. 2, p. 307.
(PS: the One- becoming- many - (spiritual concept)). (Fare thee well)
Can you cite the source material that says that? ;-)
Truth Eternal and Complete works 2 of Ram Chandra, p. 307. 'Veda is really that condition which was before the time of creation of the universe. May God give you the bliss of that condition.'
- Heartfulness meditation literature.
Fare thee well.@@schmetterling4477
Dear Butterfly - hope you are inspired - to think deep - about all these wonderful revelations - they make the heart soar i- with gratitude and awe. Fare thee well.@@schmetterling4477
Oh I'm so upset I've missed it :(
"We *only* have direct evidence of the Big Bang model from one second onwards" 😆
Poor guy was nervous at s start. He realised that he fggot the bucket analogy wrong by a factor of 10, and while wondering about it said Stars instead of Galaxies in our observable universe.
I find it a bit peculiar that my five-dimensional physics has been around for over 30 years and no one is allowed to talk about it.
It's not that no one is "allowed" to talk about it. It's probably just because people don't know, or care about your idea. If you want them to care then you need to become a part of the physics/math community. That takes a lot of work because you need to build up some trust by showing them that you've done the proper leg work. Do you have any idea how many random emails physicists and mathematicians get which proclaim to have upended the status quo? Some of them get literally hundreds every week.
31:30 somehow I can't shed the feeling that if we have to invoke 95% spooks and ghouls, we might need to reconsider our model.
Propose a working alternative. No one stops you.
@@denysvlasenko1865 There's plenty alternative ideas, but they get dismissed rather quickly.
@@SojournerDidimus So there are no better alternatives.
@@TonyTigerTonyTiger which is the better explanation of gravity: invisible angels pull you down, or air is so heavy it pushes everything to the ground? Of course the answer is neither. So why do we hold on to an idea that requires 95% of the universe to be invisible to any kind of measurement? It is perfectly possible to go with "we don't know" over an idea that is broken.
@@SojournerDidimus Logical fallacy: false analogy.
You can't provide a better explanation. You lose. Run along now, little child.
what if there was no inflationary field? what if the weakness of gravity solves that problem?
We are just tiny babies, reaching out to feel what the "toys" in our crib are. We know next to nothing so far and require much more humility!
I want to reach out, grap the moon and put it in my mouth to see if i can eat it
40:50 Why can't it just be that the universe is flat simply because there is nothing causing it to curve as it expands? 🤔
8:00 ish. He says there are 100 billion to 400 billion stars in the universe. Obviously that's not right. He was trying to say how many galaxies there are in the universe, but I think the number he gave was for how many stars are in our Milky Way galaxy, and mixed things up a bit more.
Or Jesus might say" In my father's house there are many mansions"
@@vhawk1951kl Or as Obi Wan might say, "May the force be with you"
@@TonyTigerTonyTiger Not a chap with whom I am familiar, some sort of chinaman perhaps?
@@vhawk1951kl Same for that fictional character you alluded to, in that book of ancient mythology you alluded to.
@@TonyTigerTonyTiger Poor diddums, will no-one play with poor diddums? I won't, I booted my results/children out when the were sixteen. Won't even mummy and daddy play with diddums?
I was hoping to see a theory of how the universe began. These theories explain what happened AFTER it began. My question is, starting from nothing, how did all this then get started in the first place? How does existence arise from nothing? THAT is the question...then the rest is a matter of conjecture. But how does science explain how it all started?
We don't know yet. There are several theories, but we don't have experimental data to test them (yet?)
If te words the universe are to have any meaning at all, it is axiomatic that the universe everything all things or the totality could not possibly have a beginning, because by definition the universe is unique, everything everywhere everywhen, or it is not the universe, but it is of course open to you to set out what conditions must be satisfied for whatever to attract the epithet the universe*If* you can.
Quite why the followers of the religion scientism find semantics and epistemology utterly beyond them is interesting but it may be that to ask that question is to answer it
@@vhawk1951klYour reply reminds me of a line in Wittgenstein's Tractatus: "Of that which we cannot speak, we must pass over in silence.", or words to that effect, indicating the limits of language. And in that context, I see your point. Nonetheless, we do experience feelings, and I think "wonder" is in that realm. And I can say I remain wonderous at the koan-like thought of what came before the beginning of space-time. But thanks for your reply !
@@JohnClulow Yes wonder and gratitude are feelings or the higher or finer end of the emotional spectrum. the emotions being axes or cleavers the feelings rapiers or scalpels to separate the fine from the coarse. I shall keep "of that which we cannot speak, we must pass over in silence" as useful for later in my back pocket , ta.
@@vhawk1951kl Another Wittgenstein observation from the Tractatus, I believe section 6; "It is not how things are in the world that is the mystical, but _that_ it exists." Perhaps there are some fundamental, intractable mysteries like this, Heidegger's question in Intro to Metaphysics "Why are there essents rather than nothing.", and perhaps the most fundamental question of all, what is consciousness and how can it arise from purely biological phenomena. And, of course as in the present case, "How did the universe arise from nothing?"
If the universe was initially non-uniform, wouldn't that be strange and demand explanation? Surely dis-uniformities would require a cause, whereas uniformity simply requires things to be left alone ... so I'm always going to be confused by this inflation debate I think.
Okay. I always love those talks but where is te before the big bang part. There really are interesting theories before big bang and infation. That's what I was expecting
Typical science talk with a catchy title. They spend 95% of the time covering basics that nerds would already know. That's why I usually avoid videos with titles such as "a journey into a black hole" or "what's at the centre of a black hole?" Because nobody knows yet.
Passing gas in front of the students again, I see. 😂
When something expands, other things compress.
There are no things here.
With all that primordial nuclei in such close proximity, why didn't the early universe just collapse into a black hole?
How could those primordial particles escape each other?
How could your keyboard make all those mistakes in spelling and grammar?
@@bazsnell3178 I'm farsighted and on my phone.
My theory is that previous universes end up being one big black hole, which equated to a singularly. Eventually, it cracked and our new universe was born.
Everything will crack at some point.
Good question, the answer is it depends. The universe went through several phase transitions as it expanded and cooled, so initially we had all four forces unified at plank density and uh we're not really sure happens at those energies, but it consisted of a quarks gluon plasma and everything was bouncing off each other, as it expanded the forces separated, not to mention antimatter matter annihilation etc.
It was too hot, thereby with too much kinetic energy, to have that happen.
Oh David got nervous when he said that there were about 400 billion stars in the observable universe when he meant 400 billion galaxies. Still mind-boggling, but wrong oops. The sand bucket was a great idea to help imagine.
This guy is so nervous 😶 he does mix numbers up. But it’s okay it’s practice for him
I would assume that the conditions within the Primordial Object were such that everything that stems from it had the same start. And as such, look the freaking same.
Why would you assume such nonsense? ;-)
If the words" the universe are to have any meaning, it is axiomatic that the universe is eveywhen because if it is not, it is not the universe
There is no evidence to suggest that the laws of Physics didn't exist at some stage. All theories assume that.
Just explain to us what happens with any type of bomb , before the bright flash. There you have it.
Not bad though missing some version's of the start of the universe. That and the infinite from black hole singularity and the early universe infinity are cheats. Black holes evaporate and are finite. The universe doesn't have a white hole with flow and is finite and should be used as a natural limit. Inflation from string theory has the problems of gravitational lensing and the universe as a cutoff point. Besides a few other things. The universe in a black hole 12.5 light years in diameter. It would take over 6 years from the center out before the expansion one way. Though the gravitational sphere/field can be used for FTL in a medium. The fermionic, bosonic, neutrino layers in the gravitational field are more important. The correct solutions to black holes shows the brain states one way, and how particles smear across time as radiation in one reference frame and a particle in another frame and at the same point in time. But to another point. Why do we not hear of colliding sheets making the universe? Gravity, fermionic, bosonic, neutrino, photonic as field sheets or such? Or a break away primordial mass with our universe in the cutoff limit? Or dimensions collapsing pushing energy into our universe and creating it? 6.25+ years of super luminal cherenkov radiation along with nuclear radiation if from center to outer and in high time dilation. Though gravity melting a way would work for a type of inflation for me. FTL in a vacuum from the start I do not see working. PS remember infinity for black holes is a cheat.XD
Will we ever know the origin of quantum fluctuations in the universe?
why don't you figure it out? Einstein, =P
It doesn't seem like a mystery to me. I've always thought of it as noise in the system. Like the quantum fields themselves can't remain still, so they fluctuate producing virtual particles
Well there's a bit of brilliant deduction for you….. The bits of the Universe are moving apart, so in the past they must have been closer together….. That must have taken a lot of working out?
Yes, it did, actually. You can't even imagine how many hours of observations it took to find that out. :-)
Do you have any idea how complicated such an observation is in practice?
This is only a month old, but what about the James Webb Telescope discoveries? Real life observations kill this.
The recent JWST images do not contradict any of this. Do you know what those images even mean?
@@Philitron128the JWT is seeing early galaxies that are too old to fit in with the inflationary model.
@@jimheaven Not too old, too developed. Thoze things mean different things. What JWST reveals is that we don't fully understand galaxy formation yet. At least that's the most likely thing to come out of those findings.
1 million times the rotation of milky way galaxy = WHAT!
🙏
There seems to be a lot of focus on events taking place in the first second which are inaccessible to laboratory experiment. There is a neglected area of cosmology which supposedly took place around 378,000 years later called recombination. This is the weakest part of the Big Bang theory and the speculative hypothesis explains the suggested cause of the cosmic microwave background radiation (CMBR). The hypothesis is that as the plasma cooled through the temperature of 3000 degrees Kelvin the universe went from being opaque to radiation to being transparent to radiation.
Furthermore the explanation of why we see the CMBR coming from a look back time of 13.8 billion years is that the apparent distance of the event increases by one light year per year. This implies that we are looking for a flash of radiation. Also this explanation would imply that we should see the CMBR as isotropic but we see it as anisotropic. The temperature of 3000 degrees Kelvin comes not from plasma physics but from the projection back in time of the Big Bang model assumptions.
It is well within the capabilities of modern technology to test the assumptions of recombination. If the experiment shows the hypothesis to be false then the Big Bang explanation for the cause of the CMBR is false. This is the one thing that constrains the supposed age of the universe at 13.8 billion years and we are then free to look at other models of the evolution of the universe.
Richard
CMB is in fact rather isotropic: the fluctuations are on the order of 10^-5.
> There is a neglected area of cosmology which supposedly took place around 378,000 years later called recombination.
Neglected??? There were TWO dedicated space missions (WMAP and Planck) to thoroughly measure it.
@@denysvlasenko1865 If you look at the wikipedia entry on the Milky Way galaxy you will see that the anisotropy of the CMB from our point of observation results in a velocity of around 552 km/sec relative to the CMB rest frame. Richard
the universe is groin
It that River from Slow Horses?
You must be lonely
100,000,000 grains of sand in the bucket. To get 100 billion grains you would need a thousand buckets.
The lazer's on ! Where's the party ??
Good job five stars
8:05 400 billion stars in the observable universe? This hasn't started well.
400 million galaxies in the observable universe. Everyone has a bit of stage fright once in a while. He did ok in the end.
@@isaackitone Very true, I'm just an insufferable pedant!
@@isaackitonemillion or billion?
@@sca04245 billion.
Unless the numbers have changed since I kept track, there are between 100 billion and 400 billion stars in our Milky Way galaxy, and there are some 400 billion (up to 2 trillion) galaxies in the observable universe.
If, as we believe, the universe (and everything in it) is expanding, does that mean that 'we' are too? And, if so, how can we measure this?
I think the measure is BMI
The expansion is over cosmological scales.
Over scales down to galaxies, gravity prevails and keeps things together.
I think the Expansion is limited to Space time and galaxies are not expanding but locked in a dark matter coagulation filament with condensed matter which is us being at the centre of the filamentous structure ...apperantly.... 59:03 1:00:04 1:00:19
The thought that we are "shrinking" has occurred to me. If all of our measurements are self referential then it wouldn't be apparent.
@merrickhurst4150 Like in a Fractal Universe,RE: The Geometry of Chaos, Dr Palmer.
Thanks professor, but I trust the real experts in chat more!
😂
I have a Ph.D in UA-cam Commentology, over 1000 published comments, and over 400 sci-fi movies. I can tell you, that "professor" made many grave errors
Looks choppy
static is the map.
Since 2004
I don’t get the flat universe concept. I do get the balloon one. But balloons aren’t flat.
There is no way to embed a four dimensional space-time in a Euclidean space with any less than six dimensions... so we simply can't show it as a visualization. It's like the mapmaker's problem... how to map the globe on a flat surface without distortions. That, too, can't be done.
@@schmetterling4477 So then it isn’t flat. Funny, the video said otherwise.
Drawing a map of earth accurately isn’t possible because the earth is what? Flearthers use the term.
The video said space is flat. Not round, drawn flat.
@@danielpaulson8838 It is flat in a mathematical sense (think of sum of angles in triangles). It's more of a hyperbolic surface in an embedding, but I am more than happy to admit that I can't imagine what a hyperbolic surface in six dimensions looks like. That's what the usual light cone diagrams are trying to simplify to a two-dimensional representation. Having said that, geometry in a non-static universe is a local thing, anyway. It is somewhat nonsensical to talk about angles in a triangle that will simply not "be there" in the future.
@@schmetterling4477 Using six dimensions as a scientific explanation is a logical fallacy unless somehow stated in a theory. Using it with a matter of fact tone of conviction that can only come from proof, isn't mentally far away from invoking God as an answer. You even said you can't imagine it. That should end it.
They shot laser beams from different points on Earth, at 45 degree angles into space in a crossing pattern, and the beams converged at exactly 90 degrees. They call that flat.
Yet we are in a growing bubble.
The easiest explanation, (Occam's razor), would point to, it's so huge and we measured such a small space, it just looks flat.
Like checking if the earth is round while using a two inch straight edge. In the cosmos, we are nano to the nano. And even smaller.
Flat doesn't seem viable, but stays on the table till it can be visualized. Even if that does grow to different dimensions. But I will not invoke what I cannot see or understand.
@@danielpaulson8838 This is simply the mathematical result for the "mapmaker problem" in the case of the universe. If you want to show the universe "as it is" in a flat space, then you need at least six dimensions for the most simple case and more (probably ten) for the general case.
Inhomogeneity presupposes the existence of something bigger than the universe.
So.....wtf r we talking about?
Damm you are sad 😢
The number of vowel sounds in this man’s pronunciation of the word “how” is truly amazing.
He is speaking English with a north east regional accent, and plainly has no idea what he means by the universe; like a parrot he can repeat the words but has no idea what they mean. For some inexplicable reason such creatures imagine that they can observe the universe but it never crosses their minds what nonsense that is, any more than it crosses their mind to wonder what the words the universe mean because they are stupefied by their religion that others call scientism which stupefies its adherents as all religions stupefy their adherents; they are believers - they do not*know* anything.
@@vhawk1951klyou sound fun at parties 🙄
@@stevefromsaskatoon830 Do your mummy and daddy know you are out of your cot?
you sound fun at parties@@vhawk1951kl
TLTR : we dont know.
35.29 Universe 400 Billion years old?
😂
The emotion due to that famous desk had a role, I guess.
At 35:26 - 35:29 he said "when the universe was 400 billions years old" while he meant "400,000 years old" as a rounding of the more accurate "380,000 year old" as shown on the slide.
At 8:00 - 8:10 he said "there are 100-400 billion stars in the observable universe" while he meant "galaxies" (an estimate that is growing constantly these days BTW, and depends on which study you trust the most).
At 7:31 - 7:44 he said "100 buckets" while he should have said "1000" (100b stars / 100m grains).
chaos followed by order. not difficult.
and yet I have a feeling you would be one of those people that would tell all your friends Einstein came to dinner.
Dark matter and dark energy are becoming controversial.
Extraordinary claims require extraordinary evidence - the math works just shouldn't cut it. What if the formula is wrong?
Dark matter has been observed for almost eighty years now... not sure how much more evidence you need? Dark energy is a bit more questionable, but we will have better results soon enough.
No they are not lol
I don't think you can call Inflation an established theory
It's just good that nobody of importance does. ;-)
400 billion “galaxies” in the observable universe.
What do you mean “by” that comment?
@@Amethyst_Friendin the bucket of sand demonstration, the presenter misspeaks. He says that there are 100 billion stars in the Milky Way, and then he says there are around 400 billion stars in our observable universe. This would mean there would be ~4 galaxies worth of stars, if those galaxies were similar to ours in size. I believe he meant that there are 400 billion galaxies in our observable universe (estimates range from ~100 billion up to two trillion galaxies in the observable universe)
Which can be reduced to 1/176.475 "Nitpickers" in the observable universe.
What he means, is that everyone who is worthy of their stations doesn't believe in these so called "woke galaxies", when every knows they're not far away, they're just really small, and black holes are just magnetic monopoles, designed to get you hooked on gluten.
@@charleshendry5978
Maybe he was nitpicking but maybe he was just clarifying for anyone who didn't know it was a mistake.
Inflation is a theory, not proven by any means
Yes, it's a theory. Do you know what a theory is?
No, it's not a theory. A theory is confirmed. Inflation is, as of now, a hypothesis.
What the Fk is cosmic inflation.....sounds good, but where did you get the word???
Because the cosmos is inflating... That's the best word for it.
The very worst explanation of inflation I've ever heard
totally missed the point of it alm
When he said cosmology I was thinking: a hair and make up class at RI?
too. long to get there
Recently, they have found different things. humans are too smart..
Keep finding new universe..
AI will rule after
Damn, I just thought about this 🤔, what if in an area that is devoid of atoms, a strong energy fluctuation occurs, thus creating new universes. But we cant observe it, since that area in the universe is far the nearest atom, thus we cant observe it, hehehehe
If the words the universe are to have any meaning at all, universe cannot possibly have a plural; if there is more than one, *neither could possibly be they universe all things, everything or the totality which is necessarily unique, everywhere and everywhen by definition, but fcuk what words *mean*, just use them regardless. What sufficient and necessary conditions must be satisfied for whatever to attract the epithet the universe? The child using those asinine and infantile symbols the use of which identify it as a child, has no idea?
Of course it has no idea , it is a child or it would not use such symbols; children cannot understand sufficient and necessary conditions, like a parrot it can repeat words, but their meaning is beyond the wits of children
What about the thought that the universe exists. Nothing more, nothing less. It never began, it will never end. Not meaning that nothing happens in the universe. Of course a lot happened, and still happens. Maybe a topic for another lecture? It would be surprisingly interesting to hear the philosophy about that kinda possibility.
Impossible. There had to be a point where light couldn’t travel around and atoms couldn’t stick together to explain the cosmic background we see. Only thing that works is the time before inflation and the time during and the time after. We can clearly see the moment the universe went from opaque to “clear” if you will.
If the universe never had a beginning, it would have existed for an infinite amount of time, and therefore an infinite amount of time would have had to pass for us to reach the present moment, which is not possible.
What about all the pieces of evidence that tell us both the universe had a beginning and it will end one day in the distant future? Einstein himself thought the universe was eternal at some point, but had to concede and change his mind when the evidence proved this to be wrong. The universe doesn't care how you feel it should be. It is what it is.
The moment a particle is a wave; it has to be a conscious wave!
Gravity is the conscious attraction among waves to create the illusion of particles,
and our experience-able Universe.
Max Planck states: "Consciousness is fundamental and matter is derived from Consciousness".
Life is the Infinite Consciousness, experiencing the Infinite Possibilities, Infinitely.
We are "It", experiencing our infinite possibilities in our finite moment.
Our job is to make it interesting!
If the words the universe are to have any meaning at all it is axiomatic that the universe could not have a beginning because the universe that is not everywhen is not the universe, or what you have in mind is something*other* than the universe.
No.
Any reference to the concept of time "back then" is pure speculation. We have absolutely no idea about "time".
🙏🫂🤝
Dude. I'm all like... 'sup with that, y'know? Just... wow. Dude talks funny too.
Begging of the universe is religious concept, it is not science