Cosmology in Crisis? Confronting the Hubble Tension

[@kiwiklogg]

Wendy Freedman is brilliant! She explains concepts so clearly.

[@emmapasqule2432]

she's a hottie too! her hubby is a lucky man.

[@Stevros999]

​@@emmapasqule2432so is yours 🙂

[@suyapajimenez516]

I like so much when a panelist talk so clearly about their expertise. Thanks Prof. Green for let her shine.

[@budweiser600]

"For letting her shine". How patronising.

[@thuzUNed]

@@budweiser600 Hmmm... That certainly is one way to interpret that statement. Perhaps a more generous interpretation would be: Prof. Greene has a platform that reaches hundreds of thousands of people. Prof. Greene has provided an opportunity for Dr. Freedman to share her expertise with many more people.

[@francus7227]

4:12 She sounds like the status quo of 1543 rejecting Copernicus' heliocentric theory...... Sure. She's so much smarter than I. But.... I'm not beholden to donors.

[@TheSaferHouse]

Anything with Brian Greene is an instant win. Thank you for all you do Dr. Greene!

[@ozmaile7938]

I like his presentations a lot but he has in the past jumped the shark with going way to far prompting string theory

[@Barnaclebeard]

I'm finding him hard to endure. Even as background noise while I do dishes.

[@danielpaulson8838]

Agreed. He is a top science educator and knows how to guide the conversation. Not many have hosted so many things and delivered it so well.

[@user_375a82]

He's good old Greeney - keeps the discussion around IQ 120 level and school science - that's most of us who watch this stuff.

[@FAAMS1]

A very concise and digestible explanation of the history of the Hubble tension. Lets see where the future will lead us!

[@thedouglasw.lippchannel5546]

The future is here. And there. And over there.

[@timhyatt9185]

how have I not heard of this festival before??!? Thanks Prof Greene; it's always a joy to get one of your talks and thanks to Wendy Freedman for sharing her insights!!.

[@thedouglasw.lippchannel5546]

Fabulous! Wendy Freedman has such knowledge of the subject. She is following in Vesto Slipher's and Edwin Hubble's footsteps and making many of her own. Where will the Hubble Tension and DESI and Dark Matter and Dark Energy lead Cosmology? As usual Dr. Brian Greene brings the best to the big screen.

[@DeltaV11]

And this right here is why I LOVE science. I feel like most people don’t appreciate the stories behind discoveries and scientific progress. It’s really all about finding how we get it wrong. Where are our errors? How can we correct those errors or make them less impactful? It’s about building on generations of this type of thinking. Science is truly the greatest concept we’ve come up with.

[@raycar1165]

The Thunderbolts Project has been telling the world how wrong they are for a decades and what they need to do to correct it. How can they have so many theories based on gravity without defining gravity? Wal Thornhill did define it, but you won’t hear that here. Much ❤ Love Welcome to the Electric Universe 🌎🌏🌍☯️⚡️

[@Rosskles]

​@@raycar1165 This is a place for serious discussion. The electric universe nonsense doesn't even make basic logical sense let alone scientific sense. The world is not flat, Atlantis didn't exist, Giants aren't real and Noah's flood didn't happen. I suggest you reevaluate your sources and take some rudimentary science lessons.

[@raycar1165]

@@Rosskles if you believe in black holes, dark matter and scientism, then maybe it’s time to double check your basic logical sense. Based on your assumptions you’ve obviously never taken the time to listen to, or read about the EUM. What makes gravity work in the standard model? …

[@raycar1165]

@@Rosskles also, your peace sign is upside down.

[@Rosskles]

@@raycar1165 Very telling that you couldn't even fact check that small, erroneous assumption you just made about the peace sign. 10-15 second Google search to see if you were right. Woopsiea. Like unfounded confidence without any research is what you're used too. Hmm? And "Scientism" gave me a good chuckle lol I've watched extensive talks by literal professors absolutely eviscerating the complete drivel that is the EUM. You know, people with actual PHD's who use very simple logic and the rudimentals of physics to explain how profoundly backwards it is. No surprise flat earthers love it, it appeals to people who are below average intelligence but actually think they're smart. Just because you can't understand grade/primary level logic and science, you've convinced yourself it's wrong and you are actually smart for once. Sorry bub, that just ain't the case. Professor Dave soundly trashed both flat earth and EUM in a recent debate, it was embarrassing. I STRONGLY suggest you watch a tv show aimed at beginner science about things we know for an absolute certainty are real (like black holes, we've literally got photographic evidence 😄). It might not be too late to save you from the illness of conspiracy obsession.

[@StefanMochnacki]

This was a very clear and concise introduction to the subject of determining the Hubble constant, concentrating on the fundamental calibration of the distance scale using stars in nearby galaxies (the work Wendy Freedman and Barry Madore have done, beginning in Bob McLaren's infrared lab at the University of Toronto in the early 1980's).

[@BlaTaN]

Just saying - 36mins is NOT long enough , we need longer interviews with more detailed explanations as possible. This shouldn't suffer the a.d.h.d. that the rest of the internet does. Just sayin'

[@mehridin]

probably a part of several segments released individually, like last time.

[@antoniologan7648]

100% agreed with everything you said

[@JoseLopez-w8i]

Alright Karen - just saying 😅

[@robertroy1878]

Testify!

[@danielpaulson8838]

@@JoseLopez-w8iKaren for wanting more education? Found the Trumptard.

[@carolspencer6915]

Good morning Brian and Wendy Difficult, always worth doing. Truly grateful for your shared work. 💜

[@paulmiller2741]

Excellent, entertaining discussion between two experts of a truly fascinating subject. Thank you Profs Freedman and Greene!

[@obiwanduglobi6359]

Highly appreciated. Thank you very much!

[@foetaltreborus2017]

When I think of the " Atlas of the Universe" I had in 69 by Patrick Moore.....knowledge is just expanding at the speed of light....no book could keep up ...I learn SO much these days...

[@tinkerstrade3553]

I went to school in the mid 50s, in a very rural area. 5th and 6th grade science certainly did not lay a very good foundation for the future. Sure, quantum effects and ideas were being exchanged at the level of Uncle Albert, but it never made it to the classroom. Fortunately, I was a nerd. I caught the disease at about 5 yo, when I realized that our sun was just another star, very close up. Now, reaching for 80, the fog clears a bit. I'm pleased. Thank you.

[@vslabs-za]

Awesome conversation by experts that is clear and transparent. Thanks!

[@momo19991]

This is a fantastic episode! Thank you Brian Greene !

[@Johnny-qu9op]

Loved everything from guest " questions ,and explanations ,and the patience for explaining the universe to us not so bright 😊

[@abdulkaderalsalhi557]

An amazing presentation about the amazing story of the expansion of sky in cosmology by two brilliant thinkers. Thanks, well done.

[@yeti9127]

I always find solace in such discussions whenever I find politics and social media cesspool repugnant and disgusting. 😅

[@dustynmiller2497]

Yes, because this conversation is free and 👍 🎉😂

[@Islandmidfielder]

Less politics and social media then🎉

[@jeffkilgore6320]

I remind myself that even though it is hard to deal with, we still are part of it and must engage.

[@snieves4]

Politics affect scientific funding 8(

[@MM-eu9hm]

Aye to that...🇺🇦 🇺🇦 🇺🇦 Slava Ukr4ine 🇺🇦 🇺🇦 🇺🇦

[@davidbrittenham4631]

Brian Greene has the ability to explain things in a way most anyone can understand. He also has the ability as an interviewer to guide a guest to do the same thing. I watch far too many hours of his videos, but always learn something I didn't know.

[@nunomaroco583]

Hi, Wendy one of the best, lots of knowledge.....

[@rosamrc923]

Fantastic, fantastic, fantastic! Even for the layman afficionada. Well done!

[@georgesokolov4155]

Thank you for the wonderful guest!

[@HiggsBosonandtheStrangeCharm]

...beautiful Wendy.....thank you so much.....absolutely brilliant......

[@Harry-Hartmann]

Ein sehr interessante Video 👍🏻

[@naim84]

Amazing, great information, thank you. Interestingly, I did not know about Carbon Stars and Carbon Planets too 🙏

[@shodan6401]

Oh, thank goodness. Brian Greene was told something that was comforting and reassuring about his current concept and understanding of the model of the universe. Don't want to rock the boat. And at least he found something to do after String Theory failed. I like the Science Festival.

[@GREGGRCO]

😂 be nice !! I have chased Ghosts too ! Had to ! Now we know they are ghosts. And found other things along the way.

[@GREGGRCO]

@shodan6401 Did you see his interview on The Tyson show (startalk: didn't remember name at first -edit it in here) recently ? It was pretty good !

[@GREGGRCO]

Great Video ! Thank You ! Filled in so many pieces I've had open since High School 40 years ago ! I know if I were to teach chemistry and Physics today, I'd start out with this video !!

[@genetownsend703]

The lady is great--clear and understandable.

[@Aman_Mehta_Coding]

It's a really great informative video ❤

[@markshellrude9517]

excellent. well worth a full watch.

[@deviatefishy]

That outro song is increasing my understanding of the cosmos.

[@richardsimms251]

Wonderful talk. Thank you. RS. Canada

[@williamotoole1210]

Prof Freedman has such a brilliant way of communicating concepts AND how the people who processed these findings interacted. One thing , isn't it a really good thing to not find things to work the way you anticipated? Could that be how we progress?😊

[@samuelgarrod8327]

Great stuff. Thank you 🏴󠁧󠁢󠁥󠁮󠁧󠁿

[@martink8080]

It is always interesting and fascinating to watch and listen to experts discussing their field of expertise in an understandable (as far as possible) way to the layperson. It is also always interesting and fascinating reading comments from people (benefit of doubt) who espouse theories so far out they are not in the same scientific ballpark and probably not even in the same state, all based on their own ideas of how the universe should work.

[@onehitpick9758]

Everyone still equates redshift to real motion. It is equivalent, but not formative. For us, where we would someday observe a redshift of zero would not be the beginning of time. It would be our horizon. This is clear as day. People at different places, or even at different times, would see something similar.

[@TheLochs]

As a lay person I love science and these talks are so amazing. I wish I had a better understanding of math so I could really explore physics and astronomy further. As a musician I do have a deep understanding of music which is nice. oh to be a polymath. Lol

[@nicolasperrault3363]

Very well done!

[@lplt]

new data is out today! i hope Brian has time to talk about JWST's results

[@0The0Web0]

That was great 👌

[@TheBinaryUniverse]

Clearly, the expansion rate is not linear, it has changed over time. This is the ONLY logical conclusion we can come to. Therefore, you cannot extrapolate either from the present day data into the past, nor from the early data into our present. I have to say, until we come up with an explanation for the causality of cosmic expansion, we are unlikely to solve this problem. Apparently, no one is even investigating this!

[@user_375a82]

I agree the expansion doesn't make much sense to me.

[@lipgloss202]

So good at explaining.

[@davidhine619]

The Hubble Constant value can be easily calculated from this equation 2 X one Mpc X C, divided by Pi to the power of 21 = 71 K / S / Mpc. BECAUSE the Hubble Constant is DIRECTLY linked to light speed C, this suggests the universe is NOT expanding in the way presently believed, and the expansion “effect” is actually a “distortion (illusional) effect” caused by large distances of untervening Aether. Maxwell’s equations are also based on this property of the Aether, along with Einstein’s Relativity equations, which Einstein derived from Maxwell’s original equations. So, it’s easy to see that the “base” of today’s theoretical cosmology is founded on gross misiterpretations of what astronomers observe.

[@user_375a82]

Hmmm if you're right this would be major.

[@antonychipman3088]

When we talk acoustic Doppler effect, it’s simple to rationalise a tone or pitch falling as a noisy object goes past. Optical Doppler shift is also discussed especially in telescopes and spectroscopy but are we applying it correctly to incident light? Imagine (for 1 second) that the universe is not expanding and apply a Doppler shift argument to explain apparent dilation of light frequency that is incident over vast distances. It seems logical that the frequency should dilate as a function of distance in the order of parsecs, just by virtue of converging on the eye of the observer.

[@user_375a82]

You could be right, can you explain why light converging on an observer's eye would dilate the frequency? Maybe its logic that has passed me by.

[@lanimulrepus]

Super video...

[@tkskagen]

Hello from Seattle, Washington State USA!

[@lafenelson3212]

Has Wendy's CCHP paper been peer reviewed and published yet? Last I heard all she did was give a talk that got a lot of attention without releasing her data.

[@MatrixVectorPSI]

I would think the cosmological constant isn't actually constant. It's variable, depending on the amount of cooling or "heat death" of space in that locality.

[@karagi101]

What evidence do you have that suggests that?

[@PRIYANSH_SUTHAR]

​​@@karagi101 We don't have a concrete evidence but there is a reason. The universe is maintaining the critical density all of the time even with the expansion. So one logical explanation for this could be that the cosmological constant is changing as per the requirement such that the critical density is never crossed from above.

[@MatrixVectorPSI]

@@karagi101 One thing would be the discovery of galaxies formed a few hundred million years after the big bang, before the consensus say's they should have formed. I surmise the galaxy was able to form so early because that region of spacer cooled earlier than others. And that there's a direct link between the expansion of space and the way it cools and allows the formation of stars. Another would be the big bang itself as space expanded exponentially fast. Another would be the accelerated expansion of the universe. There's lots of things actually.

[@karagi101]

@@MatrixVectorPSI The discovery that galaxies formed earlier than we expected just means that our models of galaxy formation need tweaking. The vast majority of cosmologists don’t think that it points to a need to doubt the age of the universe we calculated. And yes, galaxies formed due to slight density fluctuations because of slight temperature variations. These variations are thought to be the result of quantum fluctuations that were stretched out during inflation. Observations suggest that the increasing rate of expansion began to happen billions of years after the Big Bang. In that respect, yes, the cosmological constant has been changing.

[@karagi101]

@@PRIYANSH_SUTHAR Be more specific. Critical density for what? A flat universe?

[@toxxikanshul]

I think the person/group who will remove this tension is watching this.

[@cryhavoc38]

One thing is for certain..we don't know what we don't know.

[@robertroy1878]

Great stuff. Should be longer.

[@JagdishCVyas]

It is wonderful discussion,.

[@BenKrisfield]

The universe looking into a mirror examining itself. The simplest answers are often the hardest to see.

[@MagicTK-]

If the universe and everything is expanding, doesn't that mean our measurement equipment is also expanding? Would that change/skew the results?

[@abh2738]

Its the space between galaxies thats expanding at the moment. We are still bound by gravity inside galaxies.

[@yourstruely9896]

We are measuring the moving and or rotating speed of our galaxy more and more accurate as it seems

[@cameronmckenzie7049]

absolutely awesome

[@zpydawebb2344]

I don't see why this is described as a "crisis". Surely it's more of a "clarifier".

[@plazma1215]

Thank God that Dark matter is completely invisible yet makes up about 80% of the Universe, emitting no light or energy so cannot be detected by conventional sensors and detectors. Thank God also that there is exactly the right amount of it required to sustain the validity of the Standard Model. Where would we be without it?

[@thomaskiu4886]

I am a novice. I just failed to understand the hypothesis, as no one has indicated where exactly we are in the vast expanse of the universe. Are we in the center of universe? This should provide a more even observation or it makes no differences irrespective of where we are located. So far the hypothesis has assumed that our location DOES NOT matter. Really appreciate if any one can enlighten on the subject.

[@user_375a82]

I think its a topological type of thing, that's what I assume. There's some spinor mathematics that shows it, - I haven't checked it myself though.

[@DCGreenZone]

Yes, plasmoids and galactic scale magnetic fields will explain themselves, but you have to introduce yourself first.

[@hoerstle6636]

Could it be that time dilation isn't accounted for enough when observations are interpreted?

[@captainzappbrannagan]

Has there ever been an experiment where light was to hit a target but then the target got removed, or a light emitted where it doesn't reach anything ever (no idea how to do this). There seems to be a handshake in light before its emitted to its final destination (Finman realized this I think). I don't hear much about this but I think there's more to learn about our universe with this phenomenon. Like a block universe where all past and future exists at once and more.

[@falklumo]

Study physics and stay away from pseudo physics is my advice to you, my friend.

[@danielpaulson8838]

Here is how to explain it. If the light hits nothing, it remains a wave. If you look away from the light source and are in total blackness, you will not see the waves that are all around you.The photon needs to hit the eyeball in order to see it. The remaining wave stays in place. The blackness of some space is full of light and other electromagnetic energy traveling through and not hitting anything. Here, easier. An analogy We are surrounded by AM and FM radio waves. We are bathed in them. But we do not interact with those electromagnetic waves organically. We cannot see, hear, taste, touch or smell them. But if we use an instrument to look at them, (Am/FM Radio) we translate the energy into something that we do interact with. Music. The wave does not collapse. Many others can tune into the same one. Some pseudo science folks say things go away when not looking. Not so. We just don't interact with them and they are in fields when we aren't looking at them. I just gave two examples out of perhaps billions just like that.

[@captainzappbrannagan]

@@danielpaulson8838 This is all great but doesn't focus on the fact that light is not emitted until it seems there is a handshake between it and its future target.

[@captainzappbrannagan]

@@falklumo maybe you are unaware but the Fineman idea that light handshakes with its future target before being emitted then you may call it pseudo because you weren't aware of this idea.

[@danielpaulson8838]

@@captainzappbrannagan Ummm, no. Light is emitted without humans. Stop the foil hat baloney.

[@felixccaa]

I am still troubled by some questions: how do we know our position in the universe? given that our technology allows us to see into the universe in a distance of 10 - 20 ("Millliarden") light yrs, do we think we have been at the center of the universe from the beginning of the big bang and still seated at the very center? if not how do we know the real size of the universe - and even more so -> do we have the same redshift in any given direction? let's assume we'd devided the whole universe into 8 kubiks of the same size (4 in the front, 4 in the back), let's then asume we'd be in the 4th "quadrant" counting clockwise and quadrant 1 being from 12 - 3 o'clock (quadrant 2 being 3 - 6 o'clock, so we'd be in #4 which is situated in 9 - 12 o'clock) (#5 - # 8 would be the back counting clockwise, too) so if we were exactly in the middle of quadrant # 4 then our observation distance would reach until the center of the universe and we could calculate the real size of it being 20 - 40.000.000.000 light yrs across - and so on would then not be the redshift towards the center be negative and towards the border higher?

[@cblair1353]

there is no absolute center or coordinate grid; we're at the center of a sphere, relative to us, where we can only see things that are close enough for their light to reach us since the beginning of the universe

[@boseongcho]

I want to research the history of the expansion rate of the universe someday

[@paulbk7810]

Well done. Thank you. ---- "The effort to understand the universe is one of the very few things that lifts human life a little above the level of farce, and gives it some of the grace of tragedy." -- Steven Weinberg, from book The First Three Minutes

[@FARDEEN.MUSTAFA]

It was a great scientific show about cosmology. I have watched it 3 times and it was academic and informational. Dr Brian Greene explained the string theory and dark energy in a great way. Is the creation of God Particle (Universe) showing the greatness and beauty of quantum mechanics? Some physicists and scientists see strings, but some scientists and physicists see particles simultaneously. But prof. Roger Penrose said that string theory is not physics. The strings and particles are same matter but also different at same time and same place simultaneously.

[@JungleJargon]

We were given a mind to use it. Why aren’t scientists talking about the changing rates of causation? The amount of gravity changes the rates of causation, time and distance so the distance between galaxies is less because distance is more expanded (meaning less measures) and time passes by faster between galaxies also making things move faster. The earth is not flat on larger scales and galaxies aren’t flat on larger scales. The measurements of time and distance change on larger scales making things move faster the farther away from the center of mass that it is. Eventually the speed of stars orbiting galaxies will slow down in spite of the faster rate of causation because of less and less gravity away from the center mass. The tendency is for movement of things to slow down with less gravity. It’s just that for a while as you look at stars away from the center of the galaxy the faster rate of causation made some of the stars orbit faster. Why is it that no one is even addressing these things? They say physicists are already taking into account the effects of GR but I never hear them talking about these effects of GR. Even Albert Einstein talked about the variable speed of light.

[@speciesofspaces]

Basically, this is the same reason why I don't like sanding beyond 320 grit in woodworking because the finer and finer grits are harder to control and anomalies in the grain really start to appear making it close to impossible to find consistency.

[@jonathonjubb6626]

Really?

[@lexluthor9509]

Just dab some paint on it. No one will ever know.

[@tedscott1478]

@0:47 re. The expansion of the universe, "the rate gives us an idea of when it's gonna burst'

[@karagi101]

Question: We know space is expanding throughout our universe. Does anyone know what that implies in terms we’re more familiar with here on Earth? How much would 1 meter of space expand in one year?

[@matthewhaacke8751]

If I understand correctly, the expansion of space is not simply a set velocity (distance per time), or even acceleration (change of velocity) but rather a velocity (distance per time) per distance. So essentially things farther away are moving away faster than things closer because everything is moving away from everything. Now this doesn't, however, mean that the earth will split apart because the gravity of earth is holding it together. But it means the empty space between gravitational bounds (i.e between star systems or between galaxies) is expanding. All in all the current rate of expansion of the universe is ~70 kilometers per second per megaparsec.

[@karagi101]

@@matthewhaacke8751 That’s the Hubble constant which gives us the velocity of space based on how far away that point in space is from us. Similarly, we can determine the velocity of space expanding one meter away from us. I used ChatGPT and it gave me Velocity at 1 meter away ≈2.27×10^−21 km/s.

[@matthewhaacke8751]

@karagi101 I'd be hesitant to trust ChatGPT for mathematical calculations. It quite often broadly can communicate the conceptions but has a very poor track record for deploying the proper logic to solve the problem. Not saying it's not accurate but definitely don't trust it blindly. Additionally, while its a cool fact I'm not sure how helpful it is to physically conceive of the acceleration of space 1 meter away given that the earth isn't being pulled apart at all

[@karagi101]

⁠​⁠@@matthewhaacke8751 I’m aware that ChatGPT often gives wrong answers that look correct. It showed the calculations and they look right. For me it’s useful to picture the expansion rate in human terms. Megaparsecs are not something easily grasped by the human mind since they are way beyond human scale distances. I also understand the current expansion of space is not going to pull matter apart. The expansion would have to be much more rapid to overcome gravitational and nuclear forces. You probably know that the expansion rate is increasing and that one of the predictions is that our universe in the distant future will experience the “big rip” when even atoms are torn apart by the expansion.

[@shawns0762]

Electricity is drawn towards potential and the universe as a whole behaves the same way. I don't think this means that everything is getting bigger like a rock or a planet.

[@trebell885]

Love watching satellites above go by. The second craft I saw go by. I think i caught the reflection of the moon. Crazy.

[@squintps]

If the ever re-make the original Star Trek this guy could pull off an amazing Captain Kirk, he's got that William Shatner way of speaking.

[@ronforth3519]

Google The Forth Dimension a book containing the reason for the Hubble Tension.

[@warrenchu6319]

If the universe is accelerating in its expansion, why is there a constant, the Hubble Constant, that relates the expansion rate versus distance since the expansion rate is non-linear?

[@DanZulaica]

Nice talk and pace to think. Does the latest JSWT measurement suggestion a new, older age of the universe or does it not matter? Lots of articles give the age somewhere around 13.7 billion years.

[@jeoffreywrobel3242]

what do you think of the janus model

[@MARGATEorcMAULER]

I have a question I've been mulling over for years but wasn't sure how to word it. Wouldn't the warping of space occur in all directions around a mass at the same time and force? If so , what does that do to our understanding of gravity? Wouldn't that cancel out the effects of the warping from one direction to it's opposite?

[@MARGATEorcMAULER]

@@OOL-UV2 thanks for the reply but I don't think I described my thoughts precisely in that comment. You know that analogy of the trampoline? How the surface bends around the mass? Picture that but turn the trampoline up vertical and then upside down. The gravitational forces would be the same in every direction, not just on a flat plane, wouldn't it?

[@Lightbearer616]

Yes! If crisis means an interesting new problem.

[@showponyexpressify]

How can you adjust for dust reducing luminosity with Cepheids and Type1 Supernova..?

[@spocksbrothermadscientist5741]

What about the rate of cosmic implosion?

[@Matt-jn1dd]

did they resolve the Hubble Tension? My framework 72.3 km/sMpc matches SH0ES data 73.0 km/s/Mpc.

[@euler2718100]

Adam Riess left the chat.

[@fractalnomics]

How do we reconcile z values of 1 to 4 for galaxies and 1100 for the CMB at the same or similar location? Something is wrong.

[@JJRed888]

Why would the expansion rate not be different between the early and late universes? What if the expansion is in spherical transverse waves?

[@falklumo]

The models account and correct for changes in expansion and no, expansion does not happen arbitrarily.

[@JamaicaWhiteMan]

Excellent, thank you, but my understanding was that the size of the Hubble mirror was set by the size of the KH spy satellites, which it was a spare of.

[@karagi101]

No. It was purpose built for astronomy. There may have been limitations due to rocket size or the fact they hadn’t developed at that time the ability to unfurl multi-segmented mirrors.

[@danielpaulson8838]

Hubble was a huge, newly designed, stand alone mirror, so big that when it left the gravity of earth, it relaxed it's micro sag and took fuzzy pictures. They had to fix it with software tweaks. K-9 and 11 and more recent, (shhh) satellites do not suffer from those issues. Different design.

[@JamaicaWhiteMan]

@@danielpaulson8838 You might be wrong about that. The mirror was the exact same size as the Keyhole spy satellites. Yes. it was ground with a very precise, incorrect curvature, thus needing the correcting optics, but the mirror blank itself was a KH spare..

[@danielpaulson8838]

@@JamaicaWhiteMan They ground it the wrong shape. Just look it up. I'm not going to have an argument with someone who won't gather their own facts. The internet knows more than you or me. Use it.

[@JamaicaWhiteMan]

@@danielpaulson8838 Ahem - I've been an amateur astronomer for about 50 years. I followed all the news about the incorrect mirror as it was discovered and eventually fixed. The blank itself was a spy satellite spare. Search for that info yourself if you don't believe me.

[@jasonmills8592]

Neuroscience meets astronomical geometry. Velocity meets ferocity meets veracity.

[@singhaj]

What is the universe expanding into?

[@jonwesick2844]

As I understand it, it's not expanding into anything. It's just expanding.

[@lafenelson3212]

Itself

[@karagi101]

Nothing. Unless it’s part of a multiverse.

[@nightsmanasdf9058]

No one knows beyond the boundaries of the universe and whether there are any boundaries at all

[@lexluthor9509]

the Future...

[@benvastine257]

Logical positivism in action: sure we don’t know yet but we know we’ll figure it out, in time. This is a faith claim.

[@DonivanSousa]

yes is possible we could understand more but I think far from completely.

[@cvan1075]

How did the atmospheric nuclear explosions that contributed charged ions to the observable data discussed been eliminated/controlled in calculation. Didn’t that contaminate calculations? Hubble was above the atmosphere however nuclear explosions were exploded in outerspace affecting the ionic magnetic fields above earth.

[@michaelconley2793]

I still don't understand why the answer couldn't be, that the handles that are furthest away, are the fastest moving, because they have to be. Just like the earth is just right for life, because life like ours evolved due it to be. So if gravity is local, and some galaxies were moving faster than others and escaped to a place where there is less gravity to slow them, by nature of their existence there, they have to be moving faster or they wouldn't have made to that distance. Maybe they were accelerated after breaking free from an orbit and slingshotting, or they were moving faster from the start, but only the fastest moving could be that far away.

[@falklumo]

You have a problem understanding curved spacetime. There is no center and objects are not moving away FROM US. Space itself is expanding. Objects farer away are NOT farer away because they moved faster away from us. They APPEAR to move faster because they ALWAYS were more distant (from the VERY beginning!) and there ALWAYS was more space between us which had the opportunity to expand. So now, they appear to move faster away because the light reaching us is red shifted. Actually, a big part of the early universe had enough separation from us that it is no longer observable at all. Because the space in between expands with a speed NOW exceeding the speed of light. So, their light cannot reach us anymore. And yes, this is NOT prohibited by Einstein. This alone should tell you that you have a model too simple in your head.

[@BabarizamDK]

I didn't really get how changing the brightness of a star tells us how far it is because it simply tells us there is something in its surrounding when appears in front of it cause dimness like a planet or some other star.

[@platonicgeometryportal5567]

Has Brian Greene been promoted as a scientific minister?

[@jasonmills8592]

When imagination expands into unknown realities on higher dimensions.

[@niki7338]

Not clear to me what the methodology for using the CMB to measure expansion rate.

[@falklumo]

You need to read the papers and understand their math to understand. Eg., search for paper "The Cosmic Microwave Background and H0". To get a superficial idea, you may also search for YT videos, like from Sabine Hossenfelder who is the most accurate physics source on YT. The core idea is that you have a model which predicts the moments of the CMB and H0 is a free fitting parameter in it.

[@Orion15-b9j]

You will never get it! There is bunch of conflicting property in the official theory. For example - According to T.R. there is no reference point in the Universe... so... what is stationary and what is traveling? If you want to understand I can suggest the book - "Theory of Everything in Physics and The Universe"

[@MrBigdaddy2ya]

So what i don't understand is why do we assume that matter and expansion will travel at a consistent speed in space when space is far from consistent in its construction and composition. Some regions have superclusters with high gravity pull some regions are void of matter and have no pull. How can we know that between our measuring instruments and the target object that there arnt thick space clouds asteroids hidden black holes exploding stars regions with cmb and regions with less or no cmb all of these would affect expansion rate and redshirt right so why do we not say hey some of these calculations will always be in error because it is impossible to always know what is out there and how it affects physics in the surrounding.

[@miker252]

Was this from before JWST observations?

[@FirstDjfiresf-nn1im]

Is time çonstant? My understanding was that it is not. Slower close to large. Mass and faster in large voids. As you approach an event horizon of a super massive black hole time itself is stretched. If a black hole is not feeding or lensing a light behind it how would we know it is there? How can we measure time when it is variable through out space?

[@T6Ber62]

As an atheist I don't pray much, but I pray that there are young women watching this video and thinking about a career in science.

[@ManicMindTrick]

Why young women in particular?

[@danielpaulson8838]

Science is being demonized by Theists. They will have to be tough against supernatural ignorance.

[@T6Ber62]

@ManicMindTrick Because women are still underrepresented in the science fields.

[@user_375a82]

Maybe the further away you are the dimensions of space or time or both change so it only appears to be expanding. I am trying to include the Holographic Principle that requires a non expanding cosmos. Also it seems to relate to the incorrect spiral galaxy arm speeds that suffer a similar increase in speed that are not accounted for by normal gravitational effects. I'll have to dig out my old Amazon telescope from my cupboard and begin researching.

[@backstrapped]

I do love a “general theory” 😉

[@williamschlosser]

Try plasma cosmology, the only self-contained physical theory of the universe. No "dark" fudge factors needed.