97% of Galaxies Are Moving Faster Than Light, HOW IS THIS POSSIBLE?

I look at the galaxies that are moving away from us faster than light because of expanding space. Check out this video's sponsor brilliant.org/dos
Ninety seven percent of the galaxies in the observable universe are moving away from us faster than the speed of light. You might wonder how this can be true when one of the unbreakable laws of the universe is that nothing can travel faster than light. But this only applies to things moving through space and these distant galaxies are getting further away from us because the space between us is expanding. So the distance between us and them is increasing faster than light could travel across that space. This is also why the observable Universe is 45 billion light years across despite only being 13.8 billion years old.
#space #cosmology #DomainOfScience
Sources I used for the info in the video
[1] www.nasa.gov/feature/goddard/...
[2] en.m.wikipedia.org/wiki/GN-z11
[3] Ethan Siegel / no-galaxy-will-ever-tr...
[4] Ethan Siegel www.forbes.com/sites/startswi...
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[@Everyyoueverymiau]

This video makes me happy and very sad at the same time.

[@AquarianSoulTimeTraveler]

watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@MegaSolidninja]

@@AquarianSoulTimeTraveler 😂😂😂 no thanks

[@AquarianSoulTimeTraveler]

@@MegaSolidninja enjoy your comfort bubble...

[@robertimmanuel577]

@@AquarianSoulTimeTraveler gae

[@augmentedkeys5971]

Why?

[@gaurav_0369]

I can't believe this is the first time I have learned the difference between observable universe and sphere of inaccessibility Or even if their was a difference You're awesome 🙌

[@DylanBegazo]

Gaurav chauhan Put another example be a grenade where everything inside it is the matter that makes up our universe. The grenade itself explodes Matter is scattered everywhere. The matter that makes up the universe that we can see and interact with becomes the galaxies and super galaxies in clusters and everything else in our universe. Immediately after the grenade explosion the area within the blast radius is hot just like our universe during and after the Big Bang as the explosion continues outward things cool down. The outside environment ITSELF that our grenade exploded WITHIN in the first place IS the Antimatter itself. The matter that ends up making galaxies are all spread apart within the expansion of the grenade’s explosion. Assuming the Grenade’s explosion expansion speed is made to be equal to the expansion of the universe after the Big Bang. Does my grenade model work?

[@erwanregy6494]

@@DylanBegazo no sry I think thats a bad anology. I can think of a few things that dont work e.g. space is acceleratingly expanding after the big bang whereas a grenade explosion comes to a halt.

[@AquarianSoulTimeTraveler]

watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@MDProgramming]

Exactly 👍

[@captainjackpugh6050]

*there

[@upsilonalpha3982]

We all need some relative distance during this quarantine.

[@KokoJeuru]

A few KZbin videos tells us that Andromeda galaxy will still be in close proximity with our Milky way galaxy and in a very far distant future, the new Earth inhabitants(if they survive) can actually see & observe a real neighboring galaxy full of stars... How's that possible if we should be moving away from each other because the universe is expanding more like exponentially?

[@sindhuaggarwal4846]

@@KokoJeuru for andromeda galaxy it is relatively closer to milky way, space is expanding but for this case gravity causes there collision.

[@leeg8461]

So, gravity only works in our part of the universe?

[@sindhuaggarwal4846]

@@leeg8461 No no it is just that andromeda is close enough that gravity wins over expansion.

[@AquarianSoulTimeTraveler]

watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@ScopeofScience]

The light finally reaches the lenses of the telescopes of the *semi-intelligent* apes. lol. Well, you're not wrong, Dom.

[@amodgawade4323]

love you kurtis!!!! when will you come back to youtube?

[@0987654321mnbvcxzmor]

If a tree falls at the other end of the Universe and no one see it did it happen.Without conscience nothing means anything therefore we are really important because if we did not exist, no life to appreciate it,wow wouldn't that be strange.

[@colinp2238]

Ooooo ooooooo oooo aaaaahhh ahhhhhhh

[@rodneyboehner3007]

Unfortunately, this all flawed science. The so-called "observable universe" (AKA the cosmic event horizon) is also shrinking, AND is within the Hubble horizon IF the rate of expansion is speeding up. The only way the far edges of the universe interacts with us is through photons, which propagate at the speed of light. Thus, if those edges beyond the point where the universe is receding away from us faster than the speed of light, then that light will never reach us. Therefore this video is flawed in its reasoning. IF we presume the rate of the expansion of the universe is speeding up, then the light of everything beyond the cosmic horizon (which is within the Hubble horizon since those distant point will be caught up by a recession speed that is faster than light) will never reach us and will no longer be part of our observable universe. Even Wikipedia agrees with me. (See en.wikipedia.org/wiki/Hubble_volume ).

[@Only_God_Is_Allah_SWT]

We are not apes.

[@stza16]

I would like to attend one of these anteater parties.

[@AquarianSoulTimeTraveler]

watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@eeka_droid]

This was the most amazing video i've ever seen about observable universe, dark energy and expansion, light doppler effect and those other "basic things" to understand the universe but nobody seem to be able to come up with simple and ilustrative examples like this one. Thank you so much for this information!

[@kaitlynhollinger7526]

Thank you, this was the most understandable explanation of this concept that I’ve seen.

[@AquarianSoulTimeTraveler]

watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@sebastianclarke2441]

Thanks for a brilliant vid!! It really helped to improve my understanding of the differences between the "cosmic event horizon" and the "particle event horizon"

[@methodinsane]

Amazing dissemination of knowledge in a nice tidy understandable "bite size" chunk. The bun analogy was great. Thanks for this. I was talking to my kids at dinner about this the other day and I sent this video to them and they loved it. Turns out they knew or your channel already although I only recently found it. Great channel. Again thanks.

[@diorynovis]

While our body's ability to travel is shrinking due to covid lockdown, this video makes our imagination expand.

[@onlypranav]

@Want some corona ? I know you are trying to be funny with that username. But it's not really And yes, I am throwing some shade your way

[@AquarianSoulTimeTraveler]

watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@brendawilliams8062]

Kirchhoff ‘s law can give you a challenge. Lol

[@alainrostain4697]

Absolutely brilliant. Dominic and his team are doing outstanding work in helping increase understandability.

[@korakys]

And now you have blown my mind too with that information about more and more of the universe becoming observable.

[@TimondeNood]

Wow, I think you really did a great job at explaining this matter. I finally get a bit of a grip on it! Thank you so much

[@VeriVeronika]

Its so painfully tragic how the more of the universe we can see, the less we can ever hope to even signal. Very humbling.

[@smokey04200420]

What’s painful is the inaccuracy of this video.

[@Monduras]

@@smokey04200420 how so?

[@zealandia5668]

According to an estimate done by the scientists, there are approximately 71 planets hosting intelligent life in the Milky Way Galaxy, including us. If each intelligent life has a life span of 10,000 years, on average, we could be able to communicate with one alien intelligent life one time during our life span (if we are lucky to find one soon). So basically, the interstella communication would be something like this: Earthings: Hello, we are humans. We come from Earth. Alien intelligent life: What's up, bro? End of conversation.

[@ringoisacandyapple]

Like a big joke 😭

[@Acke1974]

One of the best videos thank you! I never seen it from this point of view. Thank you!

[@hughjasse4047]

I can't get my head around, "Space isn't expanding into anything (like the oven). it IS everything". I mean, there has to SOMETHING outside for it to expand into, right?

[@and_I_am_Life_the_fixer_of_all]

No one knows. This could also be all a simulation or something we can't even imagine.

[@grantandrew9308]

there was nothing once, why can it not expand forever further into nothing ?

[@pneumaniac14]

I will never understand this notion that there has to be more than what we know. There doesnt have to be something before the big bang, or anything outside the universe.

[@autohmae]

@@pneumaniac14 if it's all past our observable universe than we just don't know. Just lots of and lots of unknown.

[@johntate6537]

Well no, there doesn't have to be anything to expand into. This is to do with a concept called intrinsic curvature. If you draw a triangle on a piece of paper, the three angles at the corners will always add up to 180 degrees. This is consisten with a set of axioms written down by Euclid about 2,000 years ago. However, one of those axioms - the parallel line axiom - was always considered suspect. For most of that 2,000 years, mathematicians debated whether the fifth axiom couldn't in fact simply be derived from the others. In the 19th century, it was finally realised that geometries could be constructed that defied Euclid's Fifth Axiom - non-Euclidean geometries. The simplest of these to imagine is the surface of a sphere, like (approximately) Earth. The breaking of the Fifth Axiom leads to triangles that, in the case of the sphere, have internal angles that always add up to more than 180 degrees. For example, the angles between two points 90 degrees apart on the equator and one of the poles will all be 90 degrees giving a total of 270 degrees. The point here is that you can redefine the concept of curvature now by simply looking at how angles behave and not looking at the 3-dimentional shape the surface forms part of. This is intrinsic curvature. What intrinsic curvature is saying is that when you measure your way around a space the results diverge in some way - are greater than or less than - the results you would expect if the space were Euclidean. Intrinsic curvature is therefore about how you measure things within a certain space, not about the description of the embedding of that space into another, higher-diminsional space. If you add to this the concept of spacetime, you get the possibility that, again, the measurements of the differences in space and time of various events will not necessarily behave as you would expect if you made the normal Newtonian assumptions of Euclidean space and a universal measure of time. This is precisely what happens when we shift from Newtonian physics to Relativity. The ways that we describe distances and times changes because the Newtonian model does not accurately describe what we actually observe in the universe around us. It might be best to think of intrisic 'curvature' as a metaphor. What it says is that the relationships between distances and times in our universe behave AS IF they were part of a higher-dimensional object. However, nothing that might be happening off this surface has ever been shown to have any influence on what happens around us. The extra dimensions only exist in our imagination. The curvature is just a description. When distances and times behave in a way that is non-Newtonian we describe them as being 'curved' but all we are really doing is using a metaphor to create a mathematical language that allows us to describe what is going on. All that's really happening with an expanding universe is that the distance between two points is not fixed but increases with time. That's it. Space is just getting bigger. If you left two objects deep out in space outside of the effective influence of the gravitational attraction of any massive objects and you just left them there, they would slowly drift apart due to the expansion of the universe. No force would be involved. They would just get further apart because that's what our space is doing. Yeah, that's long. Not sure it makes anything clearer, but I hope it does.

[@charlessnyder1839]

It makes me sad that E. T. could never phone home, thanks to the expansion of the universe. 😢

[@daviddavidson2111]

Good point. There's no hope for us, we can't even get trains to run on time.

[@zealandia5668]

According to an estimate done by the scientists, there are approximately 71 planets hosting intelligent life in the Milky Way Galaxy, including us. If each intelligent life has a life span of 10,000 years, on average, we could be able to communicate with one alien intelligent life one time during our life span (if we are lucky to find one soon). So basically, the interstella communication would be something like this: Earthings: Hello, we are humans. We come from Earth. Alien intelligent life: What's up, bro? End of conversation.

[@pandabutter1266]

I love these videos because I can never wrap my head around this kind of stuff

[@AquarianSoulTimeTraveler]

watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@lewistimson4617]

I like your videos man. This is the first i’ve ever watched from your channel. I like how you put the puzzle in so I subscribed. Good job man.

[@Iterr]

Omg finally someone explains and SHOWS it in a way that makes sense! Love you!

[@xanamata5386]

-what is faster than the speed of light ? -space of course -and where is this light travel ? -ehm , then the only thing left since light ca not catch up with space , is time

[@jerwilliamsmith]

I was listening to this episode while cooking dinner, and I kept wondering why all of the aunts in the first example were named Ita 🤦🏼‍♂️

[@kagannasuhbeyoglu]

Thanks a lot DoS. Good subject.

[@smitakhamkar4487]

Love your content and the way of presentation

[@adrianbiber5340]

"So we'll be able to *see* more of the universe, but be *in touch* with less and less" Kind of like the story of technological progress... out of touch with Nature and each other, even though we have facetime and tele/micro-scopes.

[@AquarianSoulTimeTraveler]

watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@BrightBlueJim]

Actually, the claim is that we'll see a greater VOLUME of space, but the farthest galaxies will wink out, one by one, as they cross the boundary of our observable universe. Which by the way, is bullshit. They would have to be moving faster than light, which would make their red-shift infinite, making them already invisible. You literally could not see something traveling away from you faster than light.

[@PrivateSi]

Gravity and dark energy could be two sides of the same coin. The more mass is concentrated, the more voids expand. Growing galactic black holes are the main cause of void expansion in the model. Great Attractors that pull many galaxies to a point amplify the effect.

[@chrisscerbo5731]

great video. you explained this that made this topic very understandable.

[@alexbublea]

Beautiful thank you for this!

[@buckanderson]

I think that what's been said in the end isn't too sad, because there just always seems to be something that makes things we previously thought were completely impossible just possible. If we start to understand things better, we might find a way around the limit of the speed of light (e.g. Alcubierre Warp Drive or something not yet invented/found out about). I think whats really interesting is the rate of what we know, what we can achieve in comparison to the rate the universe makes itself harder to access. Maybe our knowledge increases less than the universe gets harder to access so we will be stuck forever. Or we might be always very slightly ahead and figure something out to overcome the problems...

[@joyhouse4625]

Still will take trillions of years for different galaxies to be out of light speed ✨️ ? Humanity maybe lucky because we're still in a period of time where you can traveller across the universe see different galaxies. ✨️

[@NondescriptMammal]

It amazes me how optimistic people are about human interstellar travel. It. Will. Never. Happen. Emphasis on the word "never". For reasons that should be obvious to anybody who gives it some serious, realistic thought.

[@buckanderson]

@@NondescriptMammal What are these apparently obvious reasons?

[@NondescriptMammal]

@@buckanderson Well for starters, the nearest star from our sun is about 25 trillion miles away... at the fastest speed ever achieved by a manned spacecraft, that trip would take about 110,000 years. We haven't even put a man on the moon for 50 years... there is some optimism about sending humans to Mars, which remains to be seen... but even that is literally a million times closer than the nearest star. A spacecraft that could deliver an adult human to that nearest star within a typical lifetime would have to travel well in excess of 50 million miles per hour, and accelerate to that speed without killing the occupants. Those are only the fundamental problems that would have to be overcome, there would be any number of logistical details beyond that, many of which would be non-trivial in themselves...

[@NondescriptMammal]

... and even if that can be achieved, and all the problems worked out to do it safely and successfully... and that is a much bigger "if" than most space travel optimists are willing to admit.... the practical matter of the almost certainly enormous expense involved would also be a consideration not to be ignored.... How do you justify that expense, when only a select few guinea pigs... oops, i mean humans, sorry... would be able to make this perilous and risky and untested journey, meanwhile the political will would have to exist to force the rest of us to pay for it..... shall i continue? Would you like to explain the realistic side of the argument for being optimistic about it?

[@Bullshit_Media]

00:00 you made bread last time.

[@domainofscience]

Haha good point! I like keeping it fresh :D

[@Bullshit_Media]

@@domainofscience Indeed;D But that good that;)

[@AquarianSoulTimeTraveler]

@@domainofscience watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@hanthony624]

@@AquarianSoulTimeTraveler stop replying that to every comment, you are reported for spam

[@anexoticidiot2548]

I loved this video. keep up the good work

[@scarletarchers9034]

Brilliant!!! Just discovered your channel...easily digestible 101 to quantum physics, science & the universe in the loveliest of voices!

[@kaiwan66]

[Quran 51.47] And the heaven, We built it with craftsmanship and We are still expanding.

[@vasile.effect]

And how exactly does light travel in a space that expands faster than the speed of light ? How can that light ever reach us if space moves the light away from us as it expands ? If a car travels with 100kmh on a road that is expanding with a speed >100km/h in the opossite direction, will that car ever get to the end of the road ?

[@thesuncollective1475]

Nice you explained this fundamental conundrum pretty well it makes sense

[@artherladett442]

Totally floored by this. Thanks 👍

[@MATropez]

In distant future though won't expansion of observable universe hit the end when light from distant galaxy will not be fast enough to overcome expansion of space between photon and earth ?

[@mehmetugur2924]

yeah i wonder too

[@kimjunguny]

Yes there is a point where our universe stops expanding. Only in 62 billion years. And eventually one day the only thing in our observable universe will be the milky way around us. Of course that's a time very far away.

[@TheZenytram]

Seach for Big Rip.

[@TheZacdes]

@@kimjunguny There is no way to predict this:/ Let alone in 62 billion years:/ The space between galaxies is expanding at a faster and faster rate the farther you go out. Just because just about everything has receded past the observation horizon does not mean it will stop expanding,lol. Just because it is no longer visible to "us" means nothing as far as the universe is concerned. Eventually things will be spread out over such a huge area that the Milky way will be all we can see. The universe will keep going till all the hydrogen is used up making stars, they die out, leaving cold cinders. It will just be VERY much larger by then:/

[@philipthompson117]

@@TheZacdes how do we know that it is still expanding if we can't see it. Might it be like an elastic band which stretches to a certain point and then snaps back. If it collapses back faster than the speed of light we will never see it coming!

[@adamghosh4010]

Things to use to work this out (I think): -Time since big bang -Red-shifting of light -Shrinking sphere of inaccessibility -The fact that distance of galaxies from us can be measured through red-shifts -Expansion rate of space (70 km/s) idk what to do with these facts but I'm pretty sure that these are needed (apart from maybe sphere of inaccessibility)

[@AquarianSoulTimeTraveler]

watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@DMSJagXK]

Some people think that light can travel faster than c (300,000,000m/s). If light travelled faster than c, then it would violate one of Einstein's postulates within his Theory of Special Relativity. In free space, wherever you are, the velocity of light is c. 2 stationary objects can have a velocity of 0m/s and yet move further apart if the space between those 2 objects is expanding. The expansion of space has no effect on their velocity since velocity is displacement from its original point divided by time. Since it has not moved from its original point, even though its position has changed relative to things around it, its velocity is zero since relative to its own position it has not moved. Now if we had an observer looking at those 2 stationary objects, they would have a relative velocity to the observer because they are moving relative to them, even though both objects still have a velocity of 0m/s. This is the exact same for light, the expansion of space has no effect on the velocity of light. The reason why some people think that it is possible for light to travel faster than c is to do with their confusion with the apparent velocity of light to an observer, rather than the actual velocity of light. If we consider objects that were actually moving within an expanding space, or just relatively moving to each other as a result of the expansion of space, then we would also have to take into account Special Relativity, since such objects will experience time dilation compared to time on Earth. The velocity of light would still be c. Time travels more slowly on moving objects, but in 1 second of wherever you are in the Universe, light will travel 300,000,000 metres. Did you know that there isn't enough energy in the Universe to get even a single electron to reach the velocity, c, of light?

[@jamesdodd2977]

@@DMSJagXK Have you seen the new pictures? Venus is blue!

[@henriquee67]

i have never ever seen some pretty damn nice explanatin about some subject that actually gave me more questions, i somehow get i more now, but at the same time i am more confused about some things, so intrigating, so awesome, thanks for sharing this!

[@emeraldeyes9565]

Good video - thanks. The last part is a bit of a head banger. I'll have to think about it - but not too hard!

[@muhllandschaft]

So the rate of expansion is 70*10^3 (m/s)/Mpc That gives the distance of the galaxies moving at exactly the speed of light away from us as c/(70*10^3 (m/s)/Mpc)=1.4*10^10 ly (1Mpc = 3.26*10^6 ly) The volume of the sphere of accessibility is V1=4/3*pi*(1.4*10^10 ly)^3=1.15*10^31 ly^3 The volume of the observable universe is V2=4/3*pi*(45*10^9 ly)^3=3.82*10^32 ly^3 (V1/V2)*100=3% which is the part of the observable universe that is accessible to us. If we assume that galaxies are distributed equally in the observable universe, then 97% of them are inaccessible.

[@f.jideament]

Which is why I'm here to say F you to all of you, because you all so special for me.

[@haroos]

The more i see these videos, the more i think physicists don't realy know what they are talking about.

[@smokey04200420]

The one thing Einstein said about relativity (how to add relativistic speeds) he failed to do. Had he added the velocities correctly, he would find that NOTHING not even space itself TRAVELS FASTER THAN LIGHT!

[@mashrafinafi6683]

great videos i love to learn from your videos

[@universeandscience5791]

Your explanation is awesome. Love you from India.

[@Staroy]

Loved this video even though I'm familiar with the concepts. Have you read the three-body problem, if so how did you like the science and speculative sci-fi in it? Btw you should get on a zoom podcast with Lex Fridman!

[@richtourist]

I've never understood why when the space expands the measurement of space doesn't expand with it? I mean, if I had a long ruler (say one of those 100 parsec ones), and it was set with a convenient galaxy at each end, and then space expanded, why wouldn't my ruler expand along with everything else? If the space between big things is expanding, then why not the space between all things? Why not the space inside atoms; inside electrons? In other words, why not the space inside my ruler; which would mean that space would seem to be constant. I guess the speed of light would have to be changing, then?

[@muhammadharis9996]

YOU ARE THINKING WRONG IF YOU HAVE A RULER WITH A GALAXY AT EACH END THEN THE RULER 📏 WILL REMAIN AS LIKE THAT BUT THE GALAXIES ARE NOW BE FAR AWAY AND WILL BE NO EFFECT ON RULER BCZ GALAXIES ARE NOT LINKED JUST AS THE WHOLE RULER IS LINKED BY INTERMOLECULAR AND INTRAMOLECULAR FORCES BW THE ATOMS ,MOLECULES WHEN THE RULER WAS CONSTRUCTED ...IT CANT EXPAND GALAXIES will now not touching the edges of RULER but attained more distance as the space has expanded

[@muhammadharis9996]

Distance bw nucleus and electron doesn't increase although space expansion bcz there is electrostatic force of attraction bw them

[@nightfallgaming535]

Thanks for the education!

[@omjethva886]

This video gave me a rollercoaster of emotions🤪, marvellous content🙌💯❤️

[@richardjanowski7219]

So if it's outside of the observable Universe we'll never be able to see it as it is NOW, but might eventually see it as it was?

[@grantandrew9308]

outside the observable universe means .....So, no., they do not come back once gone, they're gone forever

[@danielolivenca388]

And what this sphere of inaccessibility does to Fermi's paradox?

[@TheZenytram]

Nothing

[@ComedycopterDrake]

Great information

[@sikharintonkladkhem745]

Your channel deserved more views.

[@narenrai4884]

Question: If the universe is expanding in 3D, then how come we still locate the stars who seems to be in tact since the days of pyramids? Just curious..

[@user-mb2bh7yk7p]

based on my understanding, the reason is because these stars are in our galaxy. What travels away from each other are the galaxies. So, every galaxy has its own located stars. The shape of a galaxy is the total lights of its own stars.

[@user-mb2bh7yk7p]

I might be wrong, but this what I understood 😃

[@pennymac16]

tl;dr - Expansion of space is not fast enough for the stars in our galaxy to become unobservable by us. What @شش ششش wrote is half of the answer: The stars we observe are the ones in our galaxy. As was explained in the video, something must be sufficiently far away for it to "move" away from us "faster than the speed of light" due to all the space between it and us expanding. The closer something is to us the less space there is to expand, meaning it "moves" away slower than something farther away. And since the stars in our galaxy are so close to us (compared to galaxies far, far away), meaning there is relatively little space between them and us, the expansion of space has little effect on whether we can see them or not. The light emitted by them doesn't have to travel much farther due to the expanding space between us and them because the expansion of space is not really that fast. (The Milkyway Galaxy is about 100.000lys across. Then, from one end to the other, space expands at the rate of about 2,17km/s, much slower than the speed of light at about 300.000km/s.) In fact: If something is close enough to something else, their mutual gravitational attraction may cancel out the expansion of the space between them or even beating it, meaning they will move closer to each other over time due to gravity bringing them closer rather than further away from each other due to the expansion of space.

[@davidamoritz]

Also a few thousand years is not even a blink in cosmic historical scales.

[@nadeemahmad-xn4ov]

..expansion is in relative motion to the galactic movement of our solar system...which is cancelling it's effect ..so constillations are still there where they were 2400 yr back. My theory is ..time is slower beyond our galaxy..

[@encinobalboa]

If one beam of light is traveling in opposite direction of another, relative to each other, the speed is double.

[@raney150]

Despite the counterintuitiveness of it, from each beam of light's perspective, the other is still only going the speed of light, not twice the speed of light like you might assume.

[@encinobalboa]

@@raney150 If two light sources are traveling at light speed in opposite directions, they will not have any perspective of each other.

[@jorgepeterbarton]

Nope. You need to know Special Relativity. Its whole point is to preserve the speed of light. From a stationary reference frame there is no perception of 'double speed', its just two objects moving at c. From a moving reference frame (oh, assume 9.99999% or whatever) then that is where we classically sum relative velocities. E.g. a car driving away from another moving car- the stationary observer perceives actual velocities unsummed only. The cars perceive sum. So from the moving near-c frames time dilation and length contraction deal with it... that's all. Contrast to universe expanding we ARE in such a moving frame and yet it is space expanding so relativistic effects do not occur

[@encinobalboa]

@@jorgepeterbarton Perhaps my initial thought needs better framing. An observer traveling at the speed of light cannot see a light source traveling in the opposite direction at the speed of light because the light emitted can never reach the observer. So, anytime two objects traveling in opposite directions with each object not exceeding the speed of light but with relative speed exceeding the speed of light cannot be observed by each other. This scenario preserves the speed of light.

[@dencybk]

Your explanations are supercool. Thanks. Keep up the good work. I Don't know how many galaxies are there in the universe though..😄

[@luchin9198]

What a nice video. Keep going please :')

[@edeneden97]

Expansion rate = 70km/s per MegaParsec Speed of light = 300,000 km/s Distance to reach light speed = 300k/70 = 4285.7 MegaParsec In light years = 4285*3,260,000 = 13.97 billion LY radius of universe = 45 billion LY Ratio of spheres = 13.97^3/45^3 = 2.99% So 97% is faster than light!

[@altayardicoglu5741]

I guess you may want to change the title into The Galaxies Moving Away Faster Than Light or sth.

[@TheJuthika]

This video is really simple but elegant with its content. I am looking forward to see more videos like this. I would love to see u explaining Planck constant for instance.

[@nospam-hn7xm]

Interesting, thought provoking theory. Thanks for sharing.

[@daviddredge1178]

This is an excellent video!

[@CaptainBohnenbrot]

So here's the deal: things we can access is earth itself, the moon, and mars. These are 3 things. 3 is 3% of 100. And 100-3% is 97%, which is the amount of inaccessible galaxies. qed

[@philoso377]

Edwin Hubble mental flaw. Principle and practice : (true) Higher the muzzle recede velocity (causes) the projectile to reach further out (effect) Principle and practice : (false) Farther reached projectile (causes) will recede at a higher velocity from a present location (effect) Edwin Hubble published that (1) Higher red shift, higher recession (causes) the galaxy to reach further out (effect). While making a 2D chart Edwin, mistakenly placed the (cause) on y-axis while the (effect) on x-axis. How could a man like him made such a mistake, yes he is that kind of man. Such mistake soon be taken as a basis for his next theory months later. Months later : after his paper published, Edwin review the same chart again, only this time he pick x-axis as the (cause) and y-axis as an (effect) for his new theory (2) below. (2) further reached galaxies (causes) a higher receding velocity at current location (effect) Edwin continues ... at a higher receding velocity, the galaxy will be relocated further, once there it gain a new higher recession velocity to a new further location continuously accumulating speed and distance ... until receding velocity exceed “c” therefore it suddenly the galaxy disappear from an earth base observer ...... If you can understand his thought process above you may agree that Edwin has a minor mental problem or willfully ignorance, fail to recognize that (cause) and (effect) is a one way process that can not go in reverse order. And yet 99.999% scholars today take it for granted - as if that is real. If we can’t think correctly or given up thinking, all we can do is either, to keep learning or keep composing, junk science.

[@niro56]

I see your logic but his explanation works, yes? I mean even if Andromeda disappeared today we wouldn't find out till millions of years, would still see it in the sky..

[@TheScienceBiome]

Wonderful video!

[@domainofscience]

Thanks! :)

[@AquarianSoulTimeTraveler]

@@domainofscience watch my videos about accelerating expansion of the universe and how it is dark matter creating an illusion of accelerating expansion by absorbing energy that pass through the dark matter and increasing its matter exponentially causing the illusion of accelerating expansion!

[@user-fx7pj3sk1r]

Very simple explanation and easy to understand ....this how you teach science to love science

[@higherbeingX]

As per Hindu mythology Universe is 311 Trillion years old

[@jelt110]

Given that _fully formed_ galaxies with 99.99% empty space exist 13 billion years ago, I'll wager the (our) 'Universe' is _way_ older than 13.8 billion years old. Maybe not 311,000 billion years, but way older than 13.8 billion. How would _you_ form a galaxy in so little time, and more importantly, how would you clear the space _between_ the galaxies?

[@-andrea-9006]

hey i dont know if you will see this, but i just wanted to say your channel is amazing and my interest in science has re opened because of your videos :) im only 15 but i really hope to expand my knowledge so thank you for inspiring me

[@MAZA_ZatiKhayal]

I won't be able to join any courses over the said website but I would keep watching videos you upload here on KZbin, thank you very much for this kind of free and lovely material. Keep uploading. Love 💞 from Pakistan.

[@BW-xz6ol]

Thanks. Another video I’ll have to watch 50 times before I get it

[@corinnaauxtero6920]

The bitter-sweet symphony of space - beautiful, mind-bending and oh so melancholic!

[@En1Gm4A]

Thanks, finally understood it 😀

[@hubertwilliam6133]

What a usefull channel. I can understand more about Universe

[@zedka5462]

Thanks you soooo much 😍

[@batoolallahham4947]

I did like the video.... Thank you 😊

[@hughb5092]

Thank you for making this understandable to us common folk.

[@R0hi]

Thank you very much. Finally I get it.

[@vasilisvita]

I do not know if you will ever read this but this video has told me stuff that I never knew . It is mind blowing that I thought I knew but this is all new information . I think many people are like me . they think that they understand but are in the dark . thank you

[@ArabPrinceKing]

It’s good that there are places in the universe we can never reach because if we reached it we’d pollute it and ruin it. Let it be pristine, let it be free. Whether we’d know it or not it’d still be mesmerising and beautiful.

[@tomkamikaze]

Beautiful!!

[@tendies]

Geat video!

[@samuelmcsinz9279]

So basically, even if we move at the speed of light, we can never travel from one galaxy to another, we simply could never catch up

[@Cat_in_Spacetime]

Ahh, I love the outro music theme.

[@Akshaygupta13]

Your videos are awesome. Which software do you use for all the animation and editing? #TheAtomicUniverse

[@bijeshmohan]

I always had this thought in mind.

[@thesunexpress]

Another reason why sci-fi movie inspired "warp drive" is such a non-starter: Wherever you "warp" to will *not* be in the same arrangement as once observed; so you quite literally haven't the slightest idea if your destination is a bit of empty space or the core of some massive star.

[@williamblake7386]

the map of music? its pretty hard i think and not really science but i was thinking about it for years and you are the only mapmaker i know :)

[@hrob6381]

One of the best videos I've ever seen

[@rahmath3305]

That means we can never ever imagine how vast the universe is!!😮😮😮

[@anayparikh3198]

I was literally thinking about this and the video popped up on my reccomended

[@katastar221]

I love this stuff! if I could do my life over, (retired now), I'd be an astrophysicist.

[@0042090]

Great video! Did you get inspired by Fermilab's latest video? :)

[@GorbonM]

Always an interesting topic, does this mean that space obeys Galilean relativity, even though SR/GR is a better explanation for things within space?

[@SurfRawFiles]

such amazing videos, keep up the good work!

[@jus10lewissr]

This is my first time seeing this channel and the graphics aren't as neat as some of the other channels, but this was still a good video nonetheless.

[@heterosapien]

The more we THINK we know about what we call the nature of the universe, the more we discover that we know much, much, less about what we call EVERYTHING.

[@joesong4700]

My waist is expanding faster than 97% of other humans.

[@skb4all]

Ganja is the solution.

[@jeevank.c6772]

Bro!! After your lecture/ explanation was over ... I immediately fell 😴 asleep... Thanks to your tranqulizing lecture I got a good sleep...👍👍👍👏👏👏💐💐💐2020/7 /26

[@alfanders]

Very mind blowing and facinating video! Just found it contradictory that more galaxies could appear in the visible universe as the current most distant galaxies are traveling faster than the speed of light and we won’t be able to see the light they emit today. So how can galaxies even more far away suddenly appear in the observable universe? I’ve seen other videos that clearly state the opposite that because of the expansion we won’t be able to see galaxies in the long distant future, so when we look out into space it will be all dark. I would be happy to get an explanation for this!

[@lacedhexes]

Some light has notreached us yet, we will see it appear in the future.

[@stephenj.schneider5185]

When you study this stuff, one begins to feel very insignificant -- and the "why" question still remains.

[@50secs]

I asked this question to one of the astrophycisit who does PBS videos. "We are certain that everypoint is a center of universe, but we don't know for a fact that where it all start expanding from and where it all is expanding into?" They responded Si Senor.

[@topoisonfungus]

What a gem of a video