Alan Guth - Why is the Universe Expanding?

[@riffsthatkill2180]

That comment about the negative energy of gravity being equal to the positive energy of matter, this making the total energy 0 is something I remember from Victor Stinger's book. He was speaking about it as a retort to the argument "why is there something rather than nothing".

[@frankienebula]

Albert Einstein came up with that..

[@avlsage]

Protect Alan Guth at all costs!

[@astro-blaster4190]

I’m very proud of Alan. He’s retained all the knowledge I taught him and has expanded and explains my theories quite well. Education works!

[@mrbamfo5000]

Congratulations Professor!

[@astro-blaster4190]

@@mrbamfo5000 thank you. The universe is enchantingly haunting and full of fruits of innumerable knowledge waiting to be squeezed. May you be blessed as you try to understand it’s mysterious ways.

[@liberty-matrix]

In another interview Alan said that he hit upon the idea of 'inflation' at home and set a personal best in riding his bike to the Stanford Campus that morning to run the calculations. Wow!

[@mysticjedi6730]

You would not believe my shock when I figured out the probability of a larger system like our own coming into existence.. the equation does not explain the mechanism from nothing but the probability and the why it came into existence.. the probability of it happening and the why it came into existence... Will be publishing work soon.. it feels like I uncovered the most fundamental answer ever... why is there something rather than nothing... Can't wait to publish it..

[@mysticjedi6730]

@DieselPower I don't see the need for stupid jokes...

[@HarryNicNicholas]

was it ccc that came to roger penrose wile was trying to remember why he crossed the road?

[@Sebrewer32]

@@mysticjedi6730 how soon is soon?

[@pathofonepiece]

@@mysticjedi6730 Keep me in the loop if possible will ya? This particular question is something that all must chase in their own way I believe.

[@NeverCryWolf64]

Thanks for expanding my mind as well as the universe.

[@Setton1000]

Remember: As can Iran.

[@Thor_Asgard_]

The simple answer would be, we dont really know. Greetings by a fellow physicist.

[@NondescriptMammal]

Good to see this said. Any true scientist would readily admit that we don't know, before launching into their wild speculations on cosmology. We. Don't. Know. And even the best speculations by the greatest scientific minds are just educated speculations, and I've yet to hear an explanation of the so-called Big Bang that wasn't full of strange assumptions that defy all our knowledge of physics, and lead to even more unanswered questions.

[@wingoreviewsboxingandmma3667]

Why couldnt dark energy become matter considering E=Mc Squared?

[@Flipson456]

What happens when you go into a black hole?

[@Thor_Asgard_]

@@wingoreviewsboxingandmma3667 Well ... Dark Energy is nothing but numbers at this point. Its an abstract concept to make a theory work. Also the term Energy is missleading.

[@rsmithabq8304]

Thank you fellow physicist , I like simple . Too many people are out there , who claim to be educated intelligent , and would rather talk in circles than state the obvious .

[@TheGmusy]

An animated explanation would be great on these videos. Thanks 👍🏾

[@darioinfini]

For all the precision and excellence of this theory, I have a 99.9% confidence that it will be proven wrong in 100 years. "It was once thought... but now we know..."

[@charlesledbetter1735]

You probably are correct, But, we must have a base to start from and grow, change, and update going forward with new information and new technology and things we just do not have available to us at this point in time. That is why I like science so much, it does not say this is the way it is and will never change, it makes new updates as new data, information are discovered. If you go back in time and look at all of the explanations of things people thought were 100% correct and we found out they are NOT CORRECT and can prove it now 100% with testing, observation and using techology and peer reveiw.

[@darioinfini]

@@charlesledbetter1735 Whatever we've proven correct today will be found to be incorrect in the future. That's how science works. It's the business of discovering you were wrong. Which means one must come to terms with the reality that you don't really know anything. You only THINK. Science to me, although useful on some level from a practical sense, needs to be taken down a few rungs. It's become a god unto itself, and it's so prone to error and if you've been paying attention, rank corruption, it really needs to be taken off the pedestal. Philosophy ranks higher than science IMO.

[@darioinfini]

@@charlesledbetter1735 I just realized your name -- are you the Indiana photographer?

[@emergentform1188]

Love it. Guth is legend.

[@USS-SNAKE-ISLAND]

Right?!

[@friedpicklezzz]

Hmmm one thing I don’t understand, which is the title of the video. If the negative energy from gravitational forces cancelled out the positive ones (net zero), why is the universe expanding and why is it expanding more rapidly? Thanks!

[@protocol6]

If you have a universe where things can change (you have time) then it necessarily expands. Imagine a circle where the radius is time and the circumference is the extent of space at that time. As time increases, the circumference increases as C=2πct. Expansion will accelerate forever but its jerk is negative (the acceleration decreases over time) and the age of the universe is therefore roughly the inverse of hubble parameter at that time. That's just a fact of geometry, something that sometime gets lost in abstract mathematics. It happens one way or another in every sensible space-time metric; even when the manifold is infinite, which can make it less obvious. The part we should be curious about is why the observed expansion is subtly different from what you'd expect from that. That's a linear expansion in a universe sans-gravity and FLRW only accounts for part of the non-linearity so you are left with a cosmological constant, the mysterious dark energy.

[@CoolBeansGG]

Love these videos so much !!

[@jeffamos9854]

You need a lot of loving

[@richardsylvanus2717]

@@jeffamos9854 You have a lot of time on your hands I see throughout the comment section

[@johannuys7914]

@@richardsylvanus2717 Hahaha!

[@NorthernChev]

This thread is LOADED with people who either didn’t listen, or don’t have enough knowledge of the details of what he is speaking of to understand, but yet still feel that they are educated enough to make ridiculously incorrect statements about what they think they just saw.

[@NondescriptMammal]

The whole thing sounds very speculative to me, and seems to be full of speculations that fly in the face of everything we think we already knew about physics.

[@eddiebrown192]

Inflation is bunk . Guthrie is a charlatan

[@misterhill5598]

Yep. Indistinguishable from science fiction.

[@mark.J6708]

Brilliant episode.

[@arthurwieczorek4894]

'Why' as in 'how come', and 'why' as in 'what for'. 'How come' as in 'what are the antecedents that cause the phenomenon under question.' 'What for' as in 'what is the purpose in mind for bringing this situation about.'

[@artmoss6889]

Expansion following the Big Bang is a curiosity, since what we typically observe following big bangs is sudden deflation with a considerable increase in entropy.

[@pmh1nic]

My understanding is the universe is not only expanding but expanding at an accelerated rate. What is causing the acceleration? Where is the source of the energy causing this acceleration?

[@DrakeLarson-js9px]

Maybe its Inversion physics??

[@GlennGlenn-n3y]

the source of the energy lies within the realms of Dr.Goof's expanding brain p.s. I'm surprised it didn't explode eons ago 🤣🤣🙄🥱

[@mark.J6708]

Oooo first I've heard someone talk about revulsion regarding gravity.... heh, so nice to hear and think of where this might lead, especially if we discover the energy provider...

[@mrbamfo5000]

That's what perked my ears up, but also he said negative energy exists. The gram of negative energy is theoretical at this point, but I had to rewind to make sure he said that all magnetic fields are negative energy. If true that means negative energy does exist. So all I was thinking was that the reason warp drives are still considered highly unlikely is that they need negative energy to work.

[@pukulu]

Alan Guth always talks in such a matter of fact manner about ideas which are so unbelievable that you're left dumbfounded.

[@v3le]

like a priest!

[@nickmerix2900]

@@v3le exactly ! Preaching the new religion of cosmology

[@joshkeeling82]

@@v3le No. A Priest uses faith. Cosmologists use observation. Two totally different things. Faith is literally based on a hope that they're right. Cosmologists observe and interpret the observations in a edifice of logical and empirical evidence based on observation.

[@joshkeeling82]

@@nickmerix2900 Read my above reply

[@nickmerix2900]

@@joshkeeling82 thats what you want to believe. But its no really the case. Most of them never even peaked into a telescope. They just parrot someone elses theory and refuse to examine any observations that contradict it. They base this theory of expansion on red shift . Halton Arp who spent more than his share behind a telescope, observed that red shift was not an absolute indicator of distance but his findings were ignored and censored . His telescope time was withdrawn and basically blacklisted for questioning the dogma. So yes in my view established theories have become religious like, and hide behind the cloak of so called science.

[@zelmoziggy]

When was this recorded?

[@magnetospin]

Where can I find the rest of this interview?

[@yerbool]

what is the name of the hypothetical particle with repulsive force?

[@patientson]

If I learn anything from Alan Guth, I will without any doubt have the uncanny ability to explain difficult ideas in amazingly simple ways.

[@eddiebrown192]

The only thing to learn from him is how to make a living off of an obviously incorrect theory . He just keeps adding more and more , but at this point , his theory has morphed into straight up bullshit 😂

[@mrbamfo5000]

@@eddiebrown192 Inflation Theory? Seems fairly mainstream lately.

[@cookieDaXapper]

....wow, it sounds like the moment our simulation was turned on.......fascinating.

[@quanphung9966]

Alan Guth, wow! 👍

[@fractalnomics]

The answer is simple, the universe is a fractal, just like everything is.

[@TheSpeedOfC]

You know when I was a kid, before I learned anything about the universe at all, I used to think "The universe is infinitely large AND infinitely small" in other words.. a fractal.

[@yp77738yp77739]

Do you ever get the feeling that Albert Camus is entrenched within the field of theoretical physics.

[@georgegrubbs2966]

Where did the initial 1 gram of matter come from?

[@hurricane7950]

That is always the prime question. Where did it start.

[@S3RAVA3LM]

From Light. Telsa -- light is a sound wave in the Ether, the Ether itself. High energized light is hydrogen. Everything are fields. I follow an amazing teacher: Theoria Apophasis. He's on KZbin.

[@aitmimounabdallah4652]

Good point.

[@quantumkath]

It was justagram in an instagram

[@georgegrubbs2966]

Now that is a great answer.

[@paviad]

Now wait a second, I think the gravitational field doesn't exactly cancel out the energy of the mass in our universe. There should be a difference of a GRAM!

[@mrbamfo5000]

That gram would be needed to kick off the next universe.

[@NondescriptMammal]

I watched this in the hope he would have some coherent explanation for why the universe is not only expanding, but is expanding at an ever increasing rate... something they didn't "discover" until the 1990s, and that virtually no astrophysicist or cosmologist expected. It doesn't have any decent explanation within our current framework of physics, so they just postulate something called "dark energy" to account for it... despite the fact that they have no real idea what it is or where it comes from or why it does what it does. The words "dark energy", just like "dark matter", don't refer to anything that's ever been observed directly or empirically, they are just there to explain away certain observations that cannot be explained otherwise.

[@BDB78]

Exactly! And also exactly why I find it difficult to get on board with these “theories.” I also feel that “theories” is a misnomer. “Guesses” would better suit these explanations. That’s exactly what the are.

[@NondescriptMammal]

@@BDB78 I totally agree. It's good to see somebody else thinks that. Sometimes I think I must be either stupid or insane for thinking it, since so many comments to this kind of video say something like, "Oh thanks for the great explanation, now I understand!" , while I sit here going "Huh?".

[@_nick_d]

That’s a deep convo 😳

[@willbrink]

Fascinating!

[@kcm9058]

Guth ! Guth ! The Guth Brings The Truth !

[@zakirhussain-js9ku]

We use laws of physics to explain BB & its aftermath. Did the BB produce laws of physics or laws of physics produce the BB? Positive energy of mass & negative energy of its gravitational field sum up to zero. When mass changes to energy both mass & its associated gravitational field disappears. Should the process not produce zero energy since their sum was zero to start with.

[@ronaldkemp3952]

I have a question. I would really like it if someone answered it. According to Albert Einstein's photoelectric effect, when light enters a proton the low energy visible light is absorbed by the proton and then radiates an electron containing light energy the proton absorbed. There is no energy gained, no energy lost. All the energy can be accounted for. This means the proton contains a limited amount of energy. When light enters the proton it cannot contain any more so the light energy radiates away as an electron. Each proton then would be considered to be at their energy limit. My question, How could all the energy and matter the universe contains today be squeezed into a singularity the size of a pea if protons can't store more energy than they already do?

[@konsum949]

Protons are not involved in the photoelectric effect, other then being present in the atoms, so your question doesnt make sense to begin with...

[@metaspherz]

According to Brian Cox, the British physicist, “Our universe is an enigma, an endless inexhaustible paradox." The first long-lived matter particles of any kind were protons and neutrons, which together make up the atomic nucleus. These came into existence around one ten-thousandth of a second after the Big Bang. Before that point, there was really no material in any familiar sense of the word. So, to answer your question, protons didn't exist prior to the BB. Nothing did, therefore, your question is moot because the laws of Physics didn't exist either.

[@TheSpeedOfC]

I believe because protons are energy but in the form of mass so size becomes irrelevant when dealing with pure energy.

[@konsum949]

@@TheSpeedOfC still no connection to the photoelectric effect, the Electron can transfer to a Photon+energi and back, and The photon can be considered bott Particle and wave. But still, even if we change out all protons for electron in your question the question still doesnt make sence for a chemist or physicist. Try to watch some videos on KZbin on duality of photon, the uv catastrophy, the work of Einstein and hertz and Planck. The term blackbody radiaton is good to understand also, if you still dont understand, atleast you might be easier to understand what questions that are left, physical chemistry is actually very interesting field, my own favourite in chemistry.

[@imranradzmi9944]

Light particles = photon ; think photography! Positive particles in an atom's nucleus= proton. The photoelectric effect describes the release of electrons from atoms (electrons are said to be in a bound state) due to absorption of photons. These bound states occupy discrete energy levels due to their attraction to the nucleus and can move up or down a level similar to moving up or down stairs. This electron emission only occurs when the absorbed photon energy is larger or equal to the energy level difference between where the electron is and the next level (or any other level above it). If the electron absorbs energies lower than this, it will simply drop back down (on timescales of nanoseconds) and re-emit the photon, in the same way that if we miss a step while stair climbing, we fall back down. Now, once an electron has escaped a bound state (is now a free electron), it is free to have ANY energy level. There is no limit. But what about all those particles in a singularity? How can they be smooshed together? Why the electron can only exist in certain energy level states when bound is described by the Pauli Exclusion Principle. For example, this principle is expressed as "degeneracy pressure" that forces collapsing stars to form white dwarfs. Now, the immense energies involved in a singularity do not necessarily maintain the structure of atoms or fermions in general (all matter particles like protons, electrons, neutrons, neutrinos, quarks). Only bosons (which are particles that mediate forces like electricity or nuclear ; one such particle is the photon) can be smooshed together (they can pass through each other just as light can) So while current physics cannot describe what occurs in singularities, presumably a singularity would be made up of bosons (and maybe mesons that do not have to be obey the Pauli Exclusion Principle). Mostly pure energy.

[@minimal3734]

Abstractly speaking, the universe is arrangements of stuff. There are two ends to possible arrangements: 1. Everything is concentrated into one singular infinitely dense point. 2. Everything is spread out evenly and infinitely thin. In the time-bound perspective you can think of 1. as the Big Bang, and of 2. as the Big Rip. Time requires these geometrical limits to manifest themselves as the force that drives everything apart, which is called dark energy. These ideas were first described in the book "Everything forever" by Gevin Giorbran. Theoretical physicists should take a closer look at his concepts.

[@terrywbreedlove]

I want meet whoever took that one gram and sparked off the Creation of our Universe. That Dude must have been brilliant.

[@michaelcrawford3796]

I'm a little confused about what the universe is? it's the observable space around us with the matter we can see ? Now we don't know how big our universe is, only what we can see is moving forward and further away from us and closer with some matter. So I'm guessing it's not expanding because that would mean it's creating new space and not expanding into a space ? We're constantly moving at a very high rate of velocity through space so how do we know it's expanding really?

[@youareliedtobythemedia]

The universe is the space everything is in. It's expanding exponentially for some reason. The size is unknown. The visible universe is a part of the universe. It's the baundary how far we can look. Due to exponential expansion it is essentially shrinking. It's space itself is expanding, the things in it are not really moving away from each other.

[@michaelcrawford3796]

@@youareliedtobythemedia yeah umm saying so doesn't make it true

[@3007Doug]

Superb discussion and theories but with regards to positive and negative energies, at energy levels of 1.02mEv we can create a positron which is nothing more than an electron with a positive charge which in and of itself defies the basic laws of physics.

[@atiqrahman7289]

Just started with ONE GRAM!! Heck, ONE GRAM to begin with.!!

[@vkpc1]

Could it be 0.1 gram actually?

[@vhawk1951kl]

Why suppose or imagine that whatever it is you suppose or imagine to be expending is " the universe"(whatever you mean by " the universe")?

[@em.1633]

This interview is ten years old!

[@BigNewGames]

I think you're right. I remember seeing it before.

[@em.1633]

@@BigNewGames for one thing, Kuhn's hair is grey now

[@TrappedinaBrain]

So is the region where the "gram that was a billionth the size of a proton" event occurred still out there? Is it possible that the inflationary expansion of our universe wiped it out?

[@tonywells6990]

That region is the entire observable universe.

[@jamesruscheinski8602]

amount of mass increases the more slow down from speed of light squared?

[@JuxZeil]

This is one of the reasons I believe it's chaos>order...not the other way around as some scientists keep saying.

[@luisfelix7989]

So easy!! It's not expanding!! It's shifting!!

[@mastrtonberry2]

Can you still say that the total energy of the visible universe is zero if galaxy clusters are no longer gravitationally bound to other clusters and are moving away from each other faster than light?

[@PetraKann]

So according to Alan Guth "something from nothing" is not possible. We need at least 1 gram of matter (or 900,000,000,000,000 Joules of energy) to "spark" the existence of an entire Universe.

[@youareliedtobythemedia]

Something from nothing is not only possible, it happens all the time. We call it virtual particles.

[@larscarter7406]

If gravity is a negative energy then you should be able to pick a stellar mass and say right here is zero on our number scale. That way you could compare other objects to it. Anyway, i was wondering about the galaxies that we cant observe anymore because they have passed the speed of light, might that be the missing mass(dark matter). I think back in the 1980s when a lot of the theories we have today were being advanced, they knew nothing could go faster than the speed of light. So it may not have even been considered that galaxies were missing in their equations that deal with matter in the universe. If part of the universes matter cant be seen, how do you count total matter in the universe?

[@metaspherz]

What many people don't comprehend is that the laws that govern our universe didn't exist prior to the big bang. Once that fact is understood most questions about energy, mass, and what it was like prior to the BB become irrelevant. The mathematical language to explain such curiosities in human terms doesn't exist...yet. That's not to say that the questions shouldn't be asked, it just means that they cannot be answered or assigned meaning using classical scientific terminology. Therefore, all explanations are, by their very nature, hypothetical and speculative. Perhaps an alien civilization a million or more years beyond our intellectual evolution may have the answers...but they remain silent.

[@misterhill5598]

The professor is trying to impress the listener by telling them a science fiction story. The listener is taken on a roller coaster thrill ride but none the wiser when the story ends. Space: If the universe started small and expand, it has to expand into somewhere. Which space does the universe expands into? What was in this space before the universe expands into it? how big would this space need to be for the entire universe to expand into? Where did the seed universe get the energy for the bang? Time For an event as big as a big bang, it would take some time for the energy to build up the bang. How long did that take, and how much energy did the bang need? Energy: Energy cannot be created or destroyed. Where did the energy came from to create the bang+expansion, and where would the energy return to afterward? Did the energy came from the seed universe itself or from somewhere else? Why must the universe expand? Why can't the universe to stable? Why can't the universe be eternal and timeless? Why can't little parts of the universe to expand or contract while the universe itself is stable?

[@sv.foamball]

All good questions, and all questions that most of the consumers of this content have asked themselves. The journey to answer those questions will leave you with the wisdom you seek. For me, just when I think I have a clue, I delve into another aspect, which forces me to reexamine my previous understanding. It's a fun exercise if you're willing to put in the work, and have the desire to learn of course.

[@misterhill5598]

@@sv.foamball no thank you, asking questions to lead to more questions sounds like a waste of time. I want clarity, not depth of knowledge. When an expert cannot explain his expert matter simply, if he keeps relying on fictions, on vague words, and throw the questions back at the questioner, then he simy doesn't understand it. he is not the expert, he is behaving like a politician who is good at beating around the bush. These "scientists" tend to think deeply but not at all clearly. This is how science slided downhill into speculations and fictions.

[@tonywells6990]

The space of the universe does not move into or through another space, the space increases in volume, it stretches. General relativity describes the dynamics of spacetime (like how it stretches or contracts), which can either collapse or expand but cannot remain stable. The other questions about what existed before the big bang, or where the energy came from have no answer at the moment, although there are some speculative ideas like big crunch or cyclic universes.

[@misterhill5598]

@@tonywells6990 this general relativity with stretching time and space sounds like someone hit their head, hallucinated and came up with the stupidest idea ever.

[@tonywells6990]

@@misterhill5598 Einstein was that genius! Ha ha

[@wieslawpopielarski8974]

strange that in a talk gentlemen haven't mentioned about black holes. Why the big bang is different from a black hole. In both cases we got a singularity and actually seems that the big bang should not happen because it should form supermassive black hole

[@tonywells6990]

The universe was expanding rapidly, which is the whole idea of inflation. That expansion carried on after the inflation period. A black hole can only form if the universe was collapsing.

[@mickeybrumfield764]

Even if we're not in total agreement about when or what the initial big bang is it sounds like we can be in better agreement that the "bang" in the big bang occurs when we turn gravity on its head.

[@chrisgriffiths2533]

At this Stage can Not Agree. First Problem :- There Simple is Not Enough Proof to Conclude a Big Bang Ever Occurred. ( Big being Too Small a Description ). Second Problem :- Close to Zero Evidence a Big Bang Would Produce the Part of the Universe We See. Third Theory :- The Movement of Everything We See is Just what is Occurring in this Part of the Universe. Everything Might be Stationary Elsewhere, We Simple Can Not See 99.999% of the Universe.

[@MaloPiloto]

I have heard that it is believed that the expansion of the universe slowed, but then accelerated about 7 billion years after the beginning due to so-called dark energy. I would like to hear more about that and how it relates to the theory of inflation…..

[@andyc8508]

@@MaloPiloto I too looked further into this, I realised inflation and expansion specifically distinguish what you're describing. Expansion is when dark energy 'kicked in' for lack of a better way of saying it. :)

[@ctrockstar7168]

If we only knew how gravity worked we could imagine how to turn it on it’s head

[@mitseraffej5812]

@@ctrockstar7168Understanding gravity will spawn all sorts of technology. Just as the discoveries by physicist of electricity and electromagnetic etc in past centuries laid the groundwork for much of todays technology.

[@ChuckBrowntheClown]

Where does the energy come from, where is it kept conserved?

[@youareliedtobythemedia]

Good question, the answer is: We don't know yet.

[@ChuckBrowntheClown]

@@youareliedtobythemedia Where is the way where light dwelleth? And as for darkness, where is the place thereof, Hast thou entered into the treasures of the snow? Or hast thou seen the treasures of the hail, Which I have reserved against the time of trouble, Against the day of battle and war? Job 38:19‭, ‬22‭-‬23 KJV

[@chrisg3030]

What about gravity behaving not only repulsively but its repulsive force increases with the square of the distance, 𝘍=𝘎𝘮'𝘮"/𝘥⁻². I don't think this explains inflation, but maybe the accelerated expansion of the universe.

[@speed3971]

If we see space-time as one, wouldn't the expansion of the universe be the same as the movement of time? Time moves forward. Space expands. We seem to at least have theories that we can manipulate but not stop or reverse either one.

[@warrenmanning7991]

The idea of the universe (ie everything) being small and then increasing in size must be paradoxical. "Everything" must always be its size.

[@griffith500tvr]

After pushing String theory for 20 years I don't believe modern theorists about the expansion of the univers

[@BILLY-px3hw]

The universe is so strange, it either takes billions of years for things to happen or a billionth of a second, and things are either mind-bogglingly large or small...Message to universe stop being so extreme

[@johnarch6876]

For it to kick-start from nothingness, there must have been some kind of differential, either in temperature or pressure. Where did that eminate from?

[@noahholland1980]

@@johnarch6876quantum physics allows for “borrowing” the energy of theoretically any particle from empty space as long as it is “paid back” via particle interactions that cancel out the original particle in a very short timeframe. I think the idea is that the energy of the universe spontaneously arose because in the near infinite set of possible things that could happen “borrowing” the energy for an entire universe can be paid for with the negative energy of gravity. That’s my understanding anyway.

[@allauddin732]

Change is good That's why we enjoy

[@jeffamos9854]

Wow ! Maybe you should make a bumper sticker

[@allauddin732]

@@jeffamos9854 🤣🤣🤣🤣🤣🤣

[@rickrobitaille8809]

We have something to learn still😁🇨🇦🌐

[@oliviamaynard9372]

Wouldn't energies that high just be a black hole? If we can't calculate the energies of black holes how can we know what will happen at greater energy and density

[@jeffamos9854]

Don’t know

[@chrisgarret3285]

We don't understand black holes at all. We have no idea what happens to the material that falls in. That's like thinking we know what a blender is but not know what happens to the food we put into it.

[@ilikenicethings]

Well, Guth said the sub-proton sized gram of matter wasn’t ordinary matter but instead a type of matter that repels against itself. And he said this special type of repulsive matter is possible to exist at high enough energies according to the theoretical framework we’ve got. That’s the idea.

[@radupaulalecu4119]

The negative energy of the gravitational field, at 7:59 is the vacuum energy?

[@chrisgarret3285]

No, completely unrelated.

[@nemethdaniel6384]

I agree!

[@radupaulalecu4119]

@@chrisgarret3285 hi Chris, tell me more, some links will be much appreciated. Thanks.

[@mikemaurer3320]

If the gram of matter was there before inflation doesn’t that mean that the universe was there when the gram of matter was there

[@joelhall5124]

Because of made up particles and matter that make the maths work, apparently

[@jaerik99]

Professor Guth is a treasure. Thank you for featuring him so often!

[@roberthutchins4297]

Very simpatico is the Prof.. Who knows - some of what he says may even be true, but we´ll probably never know. Did he explain how there was absolute total nothing - no space, no matter, no energy, no time, no rules? NOTHING !!! Pop, pop - suddenly there was something!!! Why? Why just then, not 5 minutes earlier or a a billion years later? What flipped the switch? I may have missed the explanation.

[@lifeafterdeath88]

Where is planet earth located?

[@cvcvcvc7141]

What is it expanding into ?

[@dennisduncan9594]

We are shrinking

[@mrbamfo5000]

So, isn't the problem with the Alcubierre Warp Drive that it needs negative energy to work, and nobody knows if negative energy actually exists? Didn't he just say that magnetic fields are negative energy? Wouldn't that mean that negative energy as a concept is something we already know exists? Now this gram of negative energy itself is theoretical, but he said all magnetic fields are negative energy.

[@tonywells6990]

Gravitational fields have negative energy (he didn't mention magnetic fields), which balanced out with the energy in matter. If somehow a warp drive is possible then it would require negative energy, a bit like the expansion during inflation. There is nothing that we know of that can create the necessary extra negative energy though.

[@davidwalker5054]

Why the universe is expanding is not a question we are capable of answering and even attempting to is bordering on arrogance

[@funkyfacts4175]

Did you know... Quran 51:47 We built the universe with ˹great˺ might, and We are certainly expanding ˹it˺

[@aboversite]

Start with Richard Feynman "When you say "Why?"

[@shawn0fitz]

The title alludes to dark energy, which was not discussed.

[@zakirhussain-js9ku]

Space is another form of matter which produces gravitational field. Just like massive object where gravitational force is zero at center & highest at its surface, gravitational pull is zero at every point in space but increases as you move away from that point. This force is responsible for expansion of universe.

[@pauljohnson1664]

I prefer Roger Penrose Conformal cyclic cosmology. I don't know why but I do.

[@blengi]

I think it's a bit of both. I coded a sim once that has both properties, a basic inflationary universe which evolves conformal cyclic eras embedded in a multiverse. That is multiple conformal cyclic universes exist. It kind of predicts it was inflationary competition between universes that stopped the inflationary process not some quantum transition, although there was the possibility that the internal state of the universe just collapsed into universe scaled blackhole too - there's a certain duality about those two things, so is hard to say as my sim is quite limited once inflation initiates. It also Implied should be a universes nearby us that forced the end of inflation and that generically one universe will tend to ultimately expand faster and deflate its nearest neighbour universe by stealing its energy, until some quasi steady state is reached in the far future and a new "epoch" conformally rescales things. Also predicts a basic fundamental information coupling around 1/24 for inflationary phase.

[@ERiCDrAyViN]

If gravity is repulsive during inflation, I wonder if time flows backward extremely rapidly. So now we are flowing through time as we call it "forward in time" but a lot slower so it would explain the time the universe might last to. It's undoing the rapid backflow of time. It's just something I thought of, but may be nothing.

[@rickrobitaille8809]

Wow and tell me M=mcsquared has been the ultimate experience we can imagine 🇨🇦😁

[@vivsworldtrip]

Is it at all possible instead of "reverse gravitation", "bang", or "push"... that the universe is expanding due to being "pulled" instead? I accidently did an "experiment" at home and showed how easy the universe expanded when it was being pulled. No joke. I have it on video. Just a question... is it possible? so that way there would be no need for a special particle, or energy for that matter ?

[@Pyriold]

Something would need to do the pulling, that something needs a theory on its own.

[@vivsworldtrip]

@@Pyriold thanks for the reply. I was thinking that maybe that something would be gravity from another universe or dimension? Possible?

[@Wolf462]

No.

[@billcook7483]

Your experiment wouldn't by chance be concerned with soap bubbles ??

[@vivsworldtrip]

@@billcook7483 Hi bill, thanks for your reply. Well my "accidental experiment" actually involved my beaded wedding dress, sunlight & opening a door. All by pure accident. My wedding dress was hanging on the back of my door, when the sunlight shined onto my wedding dress, reflecting the beads colours onto the wall and creating "galaxies. When I pulled the door closed all the "galaxies" moved away from eachother. So I thought, what if universe is being pulled (from an outside source) and not pushed (via inflation)? Just a thought???

[@laurenth7187]

So yeah, why was there an exponential expansion, i mean just that ? Not how there was, but why ?

[@jazzunit8234]

Actually easy to understand

[@jeffamos9854]

Why did you bother to comment

[@mikemaurer3320]

Even if the universe is expanding where did the gram of matter come from.

[@marcinnawrocki1437]

99.99% between atoms is empty space, so mayby universe is not expanding, we are just slowly shrinking. How you define distance? It is time it takes photon to travel distance at speed of light. But if they travel a bit slower you will think universe just expanded a bit.

[@MassimoAngotzi]

And now: Crackpots’ Comment section! Enjoy the drivel!

[@NikkiTrudelle]

“ a hot dense state … 🎶

[@jamesruscheinski8602]

might quantum wave(s) expand like inflation at high energies of the beginning of universe? since quantum waves have faster than speed of light entanglement, non-locality and superposition; might be quantum waves that expand for inflation and cosmological constant?

[@txdare1830]

Thats good question

[@dolfi173]

ENLOQUECIDO , ENTIENDE ALGO MUY SIMPLE , CUANDO LA LUZ NACE EN UNA ESTRELLA TIENE UNA CIERTA ENERGÍA , PERO CUANDO YA ESTÁ LEJOS DE LA ESTRELLA SU ENERGÍA ES MENOR PORQUE LA ESTRELLA QUE ESTÁ QUIETA LO ATRAE ,PERO LA LUZ PASA SIENDO SIEMPRE ATRAÍDA Y PIERDE CONSTANYEMENTE ENERGÍA , MÁS RECORRE MAS ROJIZA ES Y SI ES ASÍ TÚ DIRÁS QUE EL UNIVERSO SE EXPANDE

[@jamesruscheinski8602]

energy happens when mass travels at speed of light squared?

[@tonywells6990]

No, energy and mass are equivalent and c^2 is just the conversion factor.

[@ScottieMacF]

Think of a block of cheese with the head of a pin in the middle. Then in an instant, all of the matter in the universe came into being. That block of cheese needs to expand to accommodate the matter. It's still expanding and pulling matter with it. We look at the universe as the nothing that surrounds everything. The universe is matter that pulls and pushes other matter.

[@tolbaszy8067]

Consciousness is the "Dark Force" that expands the universe.

[@sulaimantheruvil6096]

this is something like a leaf grows , the spots in leaf are galexys

[@quantumkath]

It was justagram in an instagram

[@rodylermglez]

He'd do a lot of good explaining that "special gram" and then trying to explain renormalization by actually calling it by name, but I guess he wanted to sound extra mind-blowing... 😒

[@crimony3054]

Since it's all moving away, the center of the universe should be identifiable.

[@philproffitt8363]

Perhaps the universe is way...way big (I believe a size proposed by Guth's calculations is one sextillion times larger than the current 'observable universe') and the centre is most likely a long...long way outside of our observable universe. It would seem the chances of any 'centre' being inside the observable universe are tiny.

[@crimony3054]

@@philproffitt8363 But if the stuff further away is moving away faster than the stuff closer to us, then we can find the center.

[@crimony3054]

@@philproffitt8363 If the universe were that big then the accelerating stuff would probably look like rain falling. Instead, it's all accelerating away at an increasing pace... from what starting point? Are we back to geo-centrism again?

[@philproffitt8363]

@@crimony3054 I think it is proposed that the view from any part of the universe would be similar. From a far away place, we would appear to be the ones moving away faster. Supposedly the big bang (rapid heating up) happened everywhere in the universe at once...not at the centre. The known universe was incredibly smaller...then, rather than explosion, we're supposed to think of the expansion like stars and galaxies are like the currents in a fruit loaf, moving apart evenly as the loaf (space) bakes and rises. As we will never observe the light from the fastest moving, farthest-away objects...we could never establish if there was a perimeter in relation to which a "centre" could be calculated. There's no reason the centre should be in an area of space observable to us. Hope that makes sense. Not facts...my understanding of the popular theory. No one can prove at this time.

[@davidstrevens9170]

One gram? Maybe someone should mention the elephant in the room. I mean, I've heard of wishful thinking but this takes the cake. I sense that science feels more comfortable if the origin of the Universe is so small that we don't need to know how it got there. Maybe Dr Suess should have been a scientist. 😂🤣😂

[@quantumkath]

It was justagram in an instagram

[@davidstrevens9170]

@@quantumkath That gram I am. That gram I am. I do not like that gram I am. I do not like green eggs and ham. I do not like them gram I am.

[@davidstrevens9170]

@@quantumkath I mean... if God had ears to hear then poor God having to listen to that tripe. It's like Da Vinci having to watch a 3 year old scribble all over the Mona Lisa with a bright yellow crayon. And this guy with a PhD in astro physics and hundreds of thousands of dollars in funding. What do we have to show for it? Well... allow us to take this opportunity to declare, (with much pride in the magnificence of the human intellect), that the origin of the Universe stems from a gram of green eggs and ham.

[@davidstrevens9170]

Maybe now's a good time to use my get out of jail for free card. Or perhaps I should hold on to it for when they tell me that the Universe is just a thought-form and we're all sharing in it but because it's the same thought there is effectively only one of us.

[@chyfields]

The truth could be as simple as: if we collectively agree that the Universe is expanding, then it is.

[@xxxs8309]

Universe doesn't care what we think

[@chyfields]

@@xxxs8309 I am part of the universe and I do care, ergo, there is a part of the universe that does care

[@xxxs8309]

chyfields people thought the earth was flat and the center of the universe, how did that go

[@eriksaari4430]

i smell bs

[@walterott8228]

Um… nope. Before we knew better, we collectively agreed we were at the center of our solar system, but that did not make it so.

[@yuvarajgopal2717]

Why interviewer keep interfering while guest is explaining

[@AmatureAstronomer]

"Why is the Universe Expanding?" How could any human know the answer to this question?

[@funkyfacts4175]

Did you know... Quran 51:47 We built the universe with ˹great˺ might, and We are certainly expanding ˹it˺

[@mensaswede4028]

The universe must expand or we wouldn’t be here, since gravity would collapse everything to a singularity without the expansion.

[@nemethdaniel6384]

It is not true. Standard Newtonian gravity would cause the same expansion. Put down "particles" homogeneously and isotropically in an infinite universe , then apply a small perturbation on the position of one of it. It will result in a collapse of the stable structure, some locations would start attracting each other indeed, but most of the points around you would get further from you, thus you would see actually a "Hubble Flow", such that we also see and call "expansion". You don't even need General Relativity to get that gravitational phenomena, and it won't cause a collapse of everything into a singularity.

[@mensaswede4028]

@@nemethdaniel6384 ummm, no.

[@Tsamokie]

Inflation makes the standard model work but, BUT, where is the evidence for inflation?