Space DOES NOT Expand Everywhere 

Other top channels for the average person are: Veritasium Sabine Hossenfelder The Science Asylum Fermilab

@@_PatrickO Veritasium has had a couple of controversial videos, like the one with the self driving cars that was clearly a paid content to promote the technology. I think that type of content really compromises the integrity of a channel that sort of claims to be scientific. Still, it does have some good content but just take it with a grain of salt.

@@juezna You dislike him for a single non-science video he did? Grow up. I just searched it and saw debunking videos. It is unbelievably pathetic to get so worked up over a self admitted limited review of waymo that you think about it daily and make debunking videos. The people obsessed with hating self driving cars are disgusting luddites.

@@_PatrickO wow Patrick, you seem to have me worked out because I do spend my days with a sense of consternation for the existence of the Veritasium waymo video, and even more so, developing a deep hatred for self driving cars. Thanks. You've saved my life. And of course, I promise not to make you so angry with observations about your so beloved youtube channels ever again.

WE'RE SHRINKING!!!! 😱😱😱😱😱😱

So YOU'RE the one!

It only took them more than 3 years to get to it, but at least they eventually did, unlike others who constantly skirt around it :)

If for nothing else - this kind of information corrects all the bullsh*t we were taugh in school. I have found for the many years I've been out of school that lower level education is mostly wrong and flawed.

​@@uberfu Higher level "education" is even worse.

there is no why, only how

@@DrWhom but why 😏

it's not a bug! it's a feature of course!

Great 👍

Yeah it's actually explained by xyz, don't look into it

It's Gmail. It will reach 15gb and stop

The way humans are i find it likely that we are the equivalent of single cell infections on a single blood cell inside God.

Sounds exactly like those fractal zoom videos to me. Also, if the "unzipping" universe contains additional detail compared to the previous state, why would entropy have to increase in the positive time direction? Seems the created detail could be played against the entropic disorder so either factor could dominate locally.

I think of it more as the websites you try to hide on your browser history. Your wife or your mom (depending on your age and your living situation) accidentally finds one and they multiply as pop ups and pop unders, and expand in eternal shame and embarrassment

I don't believe it's expanding. The universe is massive and in constant movement, the movement is at such a large scale we cannot comprehend it. I think the expanded space we examine is just temporary and will later close. Think of asynchronus gears that are elipical shaped. So at certain points of time their edges can be farther or closer to one another, but the centers remain the same distance. It's just an illusionary effect.

@@robertcairone3619 Maybe more like adding more detail to the current layer, opposed to zooming in on a fractal is seeing another layer of detail.

An interesting informational perspective, though in this zip file analogy the shannon entropy never changes as the file size dosn't change, if information can never be created or destroyed then it fits quite well.

Just don't watch Moonfall. Watching it has been shown to selective kill off brain cells used for understanding physics and cosmology, in the name of willing suspension of disbelief.

It's important to remember that time-like geodesics are the paths of objects affected only by gravity and momentum, i.e. orbits, or ballistic trajectories, or falling. The motion of most stars is mostly determined by gravity, with other forces having negligible effects on their paths through space-time, meaning that stars basically move along geodesics, as do planets, galaxies, and many other things. Thus, if you think of space as made up of points moving relative to each other along geodesics (I'm not actually sure how useful this is), space is orbiting and falling into galaxies, not just pinched together and stationary, with geodesics moving parallel to each other into the future like he said in the video. (I don't know if what he said makes more sense if you think of space in a slightly different or more specific way, or if he was just simplifying.) Now, to be clear, just because almost all stars are almost on geodesics, that obviously doesn't mean that all geodesics have stars on them. Every POSSIBLE ballistic trajectory (for an object of negligible mass) is a valid geodesic, not just the ones that actually have objects on them, so some geodesics are orbiting the galaxy the opposite way from most stars, some are falling into the galactic core and coming out the other side, before falling back in and repeating this (noting that the galaxy is not a point mass), a very few are obviously falling into black holes and never coming out, and some fly out of the galaxy and never return. (There are also light-like geodesics, which light moves along when it's moving through vacuum. As for space-like geodesics, I know tachyons would theoretically move along them. I don't think they're exactly analogous to physical objects, despite Einstein's talk of "measuring rods", since physical objects are usually held together by electromagnetic forces, which admittedly move slower than light, and also because it's not clear without calculation which instants of each point in the object you're assigning to the same space-time geodesic. I think maybe space-like geodesics could be thought of as faster-than-light paths between matching ticks of clocks in different locations, but that's a very problematic definition.)

What makes spacetime infinitely divisible?

@@CMVMic Do you mean logically or mechanistically? Like do you mean "what makes you think spacetime is infinitely divisible?" or "what happens *physically* such that spacetime is infinitely divisible?"

@@CMVMic Because Matt said so ...

I don't believe it is physically possible to infinitely divide a volume of space. Physically speaking. That would be arguing that there is an infinite amount of space in any given finite volume ... I do not believe that is actually possible and that the math is a fallacy on paper.. Meaning it doesn't mean it is physically possible just because you can mathematically write it down on a piece of paper. Hence just because I can write a story about magical unicorns doesn't mean they can physically exist here and do all the magical things I say they can. I think the answer will be more in the lines of space or energy is comming from somewhere else to expand the space or volume that is in question here. This whether be from out side this Universe, surrounding spacetime and energy, or from other dimensions etc.. Like how a river cannot increase its volume or flood a region without more water beeing introduced from some other source. Basically I would argue one cannot increase a volume of space without subracting from another, or without there being some sort of equal exhange or displacement. Just like energy, I do not believe it can be created nor destroyed... Here I believe it can only expand or contract where these two physical phenomenon are physically linked or bound as a part of a single over all volume.. This to where both phenomenon directly and physically affects or impacts the other. even if the volume itself were to be infinitely vast. I could be wrong, but I have a real hard time accepting math that argues we can get more physical space from literally nothing or just by just saying we can, on paper, add and subract more space.

@@TheJackelantern well, just because a region of space could be infinitely divided doesn't mean that it contains more space than it does. That would be impossible. I don't know whether or not space IS infinitely divisible, but there doesn't seem to be anything necessarily contradictory about the idea. You're correct, just because you can write down the idea doesn't make it correct, but I see nothing wrong with the idea though.

depends what ur universe is made up of

It depends on their relative kinetic energy! If the gravitational energy is in absolute value greater than the kinetic energy, they are gravitationally bound, and the space in between does not expand. Viceversa if the relative kinetic energy is greater, they are not bound, and the space expands. By relative kinetic energy I mean 1/2mv^2 where v is the relative velocity. I'm sure you can find the distance as a function of the velocity and find out your answer with this :P

@@davidbarroso1960 yes. How much is it?

@@kaptenhiu5623 4

@@Hansengineering 4 what?

both of those things can be (and are, imo) true

Any historian who would say that is a fool. We are constantly living in the best time in human existence. Even 100 years ago if you got a cut infected you could easily die from sepsis and premature babies pretty much were either left to die and only the lucky ones were given care and put on display for the public to gawk at. Not to mention everyone was horribly racist as a matter of course. As another person on educational RU-vid is fond of saying “The past was the worst”

Cosmological Historians: This is a challenging and difficult but also extremely fortuitous time to be alive.

Boltzmann brain: Actually, thi

I don't think historians are the ones saying that. Click bate media on the other hand...

If you mean tension from the expansion of the universe, keep in mind that the electromagnetic force that holds molecules together is orders of magnitude more powerful than gravity, which is already more powerful than expansion at anything but intergalactic scales. Unless there's some fine detail with this particular setup I missed then there shouldn't be any detectable tension caused by expansion(this might change in a few billion years if Big Rip cosmology is true, but not in the here and now).

Yes, but not because the universe is expanding. The cable would bent and curved by dark matter along its entire length and this curvature would put tension on the cable. It would be pulled and distorted by dark matter all along its length.

If the cable were _anchored_ to solid objects in two galaxies on opposite ends of a large void, and those objects were somehow fixed in position relative to their host galaxies rather than orbiting the center, yes the cable would experience tension as the expansion of space in the void pushed the galaxies apart. But if the cable were free-floating, it would simply drift like any other free-floating object. In fact, given how little gravity is required to cancel the effect of "dark energy", it's quite possible that the gravity generated by the cable itself would prevent space from expanding in its immediate vicinity.

@@deusexaethera Say that the cable hypothetically has no mass...

No because it isn't anchored anywhere

I find that analogy appealing as well. The problem is for some reason the universe is NOT expanding inside galaxies. But time passes everywhere, inside and outside galaxies so if the expansion is the physical form of time passing then galaxies should expand as well as time passes inside them too. Yet they don't and that is weird. Also I have a problem with the idea of "places where there is no gravity" as an explanation as to why some places experience "growth" while others don't. Gravity is everywhere, distant galaxies still tug on each other, the effect of gravity extends infinitely if given enough time. Gravitational waves have reached us from billions of light years away (as far as I understand) so clearly gravity is everywhere, even if very, very small in some places. I really think the astrophysics community is grasping at straws to explain these phenomena. Dark matter, dark energy, places where the universe expands but others where it doesn't for no apparent reason - it's all a big mess. We desperately need a new theory that explains these without placeholders like dark matter or dark energy or space that is created in some places but not in others for no discernible reason. Expansion started fast, then slowed down a lot, now it's accelerating again. Why? We need answers. Sadly human kind seems to have slowed down it's intellectual output by orders of magnitude compared to the last couple of centuries. Why? I don't know. But it sure seems so.

@@NotYourBusiness-bp2qn I have explained my theory( various comments ,different channels) based on M=E/C2 so I will not now.(I think it explains dark energy and relapses dark matter with dark mass, indeed it predicts/requires Quantum vacuums[ no gravity] ,I call them cavitations) I wanted to mention your comment about time. Whether you believe that gravity slows time or as I do, that time causes gravity ; what is beyond doubt is that where there is heavy gravity time moves slowly. In our space time the Earth was created 4.5 billion years ago but in the much greater gravitational pool/pit of the sun we might have only been created under a billion years ago or whatever the maths says. I wonder if within galaxies space is expanding but due to gravity time is happening exponentially faster in intergalactic space. You have to look through billions of light years of exponentially faster time to even notice the expansion of space. it just might be imposible to to detect in our infinitely slower time and smaller space for that matter . ‘The kettle may be coming to the boil but one half second observation it would be hard to tell.’

There isnt such a thing as sub planck length..

Yeah, I wonder that myself. Also: does that expansive outer boundary condition slightly perturb the Schwartzchild-like solutions so that, strictly speaking, the effect is not zero but rather just too small to worry about, and in a way that's baked into the stable bound orbits such that there's no effect accumulating over time?

I had two questions, yours is one of them. The other is that, if you look to the distant past, those "parallel" lines do converge. At some point in the future do they diverge?

@@paulpeterson4216 Yes, according to GR the geodesics converge into a singularity on one side and either diverge on the other side or converge again into a singularity. Given the way space is expanding, it seems the geodesics that started at the big bang are diverging out and why we think the universe is going to expand forever.

It applies anywhere that gravity is stronger than the expansion rate, so anywhere there is mass...

Good question; If it's the flow of time increasing rather than space being created then I'd say no, we're just in a steady bubble of temporal flow, and that if we left our galaxy far away in the dust we'd simply experience time speeding up unregulated compared to our cozy home in our galaxy. No zero point of non-contraction/expansion found while on our journey.

I may not have a doctoral understanding of physics so there may be a better answer... BUT... my understanding of Planck length is that it is the smallest measurable unit of time-space and that there is neither time nor space between the Planck lengths... so there is nothing there to expand. If you grid a section of spacetime ad infinitum, once you reach Planck length and have a grid made out of them there would be no further spacetime to evaluate in those boxes. If we took that box and expand it in scale, we have just added spacetime and can now grid it down again.... these layers of the smallest boxes having to 'get bigger' for us to keep going is what leads to expansion of the universe since/from the big bang... so in a way a Planck length is a type(minor edit) of singularity too maybe?? Interested in seeing others take on your thought and my answer as well... :)

@@drunkbeaverproductions You are touching upon the key to my thought experiment which is the "gridification" of spacetime using Planck length as the basis vectors. I'm thinking these Planck length grids as "pixels" (in 2D) or "voxels" in (3D). I'm pondering how to explain (without visuals) the questions that arise from this in my head. 1st is the "can spacetime only grow by 1 x Planck length". It would intuitively seem "yes" as there is no space measurable that is 0.5 x Planck. So if this is true, what happens when the spacetime expands by odd number of Plancks? If you grow a 3D voxel space by +1 (or +3, +5 etc.) around a point, that point will jiggle every expansion by +/-0.5 if only whole number coordinates are allowed. So does this mean that the Planck length (imaginary) grid around us jiggles by +/-0.5 whenever spacetime grows by odd number of Plancks? This is probably theoretical banter, but as (ex) 3D graphics programmer one can't help but wonder about this and might this have any implications... Then again I'm happy if someone here can disapprove me at the "Universe grows by whole Planck lengths only" assumption. :)

@@pasikeranen to not break 'Planck length' the universe could only expand by EVEN numbers of Planck lengths then... which is also interesting as a concept. if you are looking at 2D pixels or 3d voxels does that mean that we maybe need to evaluate the 11th dimensional "strixels" (String theory seems to want extra dimensions we don't usually consider)??

Also gravitational fields are infinite in range, so we still need a cutoff point somewhere.

@@thedave1771 A gravitational field is just Gravitational force per unit mass. Gravitational field follows the inverse square rule, extending infinitely.

@@hyperduality2838 You have no idea what a dual, in the mathematics sense, is.

I think the answer is that Matt has put too much reliance on the Schwarzchild metric, which assumes a cosmological constant of zero. Just like the ΛCDM model's FLRW metric neglects the fine structure of the universe, but works very well on the very large scales, so the Schwarzchild metric fails to consider the large scale, but is a very close approximation on the small scales. In the intermediate region neither metric will give you an accurate result, and you need to solve the Einstein Field Equations in full. Which is to say that expansion probably does have an effect on smaller scales, but it's so small as to be completely negligible.

Isn't space bending because of the gravity and that fix the difference in expanded and not expanded space?

Maybe the big bang started in a black spot before the previous universe ended

@@osmosisjones4912 dude…

What if the BigBang started in a black hole before the previous universe ended

Depends on the geometry for said region of space.. Is going around a tile of concrete faster than simply crossing the tile? How about a parking-lot sized tile of concrete vs a sidewalk tile? Also, what do you mean when you ask, "take longer"? What sort of masses will be affecting your travel? Time is relative, so one would need a frame of reference to answer your question.

My guess is no, the universe can't expand in that way, but I'd love to hear a rigorous explanation from someone who knows what they are talking about

Light follows the null geodesic, the straightest path connecting two points. Shine a beam of light and you'll have your answer.

@@MAD-SKILLZ except there can be multiple null geodesics. Think of gravitational lensing? There can be multiple paths light can take.

Repent to Jesus Christ “For there is one God and one mediator between God and mankind, the man Christ Jesus,” ‭‭1 Timothy‬ ‭2:5‬ ‭NIV‬‬ J

"Basically" lol I love it. Thank you. Sounds great but the "basicall" makes it gold😁🤙

He's mistaken about dark energy. Dark energy is modeled by a scalar field with a non-zero value at all points in space, that exerts a negative pressure. It is present in our bodies, the solar system, etc, causing points to feel an acceleration away from each other proportional to their separation. For small things (on the scale of the universe), this is immesurably small, but there nonetheless. This causes bound systems to be a wee bit bigger than they would be in the absence of dark energy.

@@ozzymandius666 I don't think he's mistaken as much as going directly to the conclusion for the sake of time. Remember all of these videos are high level overviews; even when they say "deep dive". Because of the negative pressure spacetime curvature from a massive body is eventually negated by distance; the reach of gravity is not infinite as Newtonian gravity would suggest. Bodies that do have a gravitational influence maintain it in balance with dark energy; so they don't experience expansion relative to each other, as long as dark energy remains constant. Dark energy is everywhere, but expansion is not. Only bodies with a gravitational interaction weaker than dark energy will recede from each other. On the rubber sheet analogy instead of a perfectly flat rubber sheet, it's like one that is inflated from beneath and would have the shape of a slight mound before any objects are placed on it.

@@ozzymandius666 The video is not mistaken. There is no acceleration proportional to separation, only an average tendency for an outward velocity proportional to distance. The distance between objects only increases if they were moving away from each other in the first place. It is possible to calculate this: set up two test particles such that the velocity of one is parallel transported from the other. Calculate their geodesics. They will not diverge if the spatial geometry is flat (which is the generally accepted geometry of the universe). If dark energy worked the way you claimed, then gravitational attraction would have a maximum range and I think orbits become unstable well below that range too.

That property is defined for an unchanging space time, isn't it? In an expanding space time, that might not hold true

Planck-length units of space aren't quantized "pixels". They are arbitrary. You can measure two Planck-length units of space that overlap with each other if you want; the Planck length is merely the minimum size beyond which you can't conduct any measurements because the energy required to perform such an observation would spontaneously form a tiny black hole, erasing the data you attempted to collect.

"If you didn't vote for me, you ain't Blanck."

There is no Planck length chunk of space, special relativity forbids it.

Let's just assume that the gravity is probabilistic. Problem solved.

I had the same question. Cannot even attempt an answer, but I'm here to corroborate the question.

Add to the fact that mass was apparently more concentrated back in the day if we are to believe this hogwash.

maybe mass just slows the rate of expansion... I donno

Also, masses move through space. So in some sense there would be differences in space that had mass near them for a while without expansion, and then expansion continues/restarts when the mass moves on. That space wouldnt catch up its expansion. So space would not be uniformly expanded. I am not sure if the differences could be detected, or if there might be some latent effect due to the warping. (Crazy idea, perhaps even explaining what we think is due to dark energy but is warping of nonuniform space, for example where older galaxies rotate faster than expected.)

Good question. Actually, there is no discontinuity between them. There is a smooth transition. An analogous case is a star that collapses to a black hole. The metric that describes the interior spacetime geometry of the collapsing star is different from the metric of the (approximately vacuum) exterior, but there is a smooth transition ( again) between the two that is described within the theory of General Relativity. Something similar happens between Galaxies and the intergalactic space, etc.

@Kleos what does any of this have to do with the comment you just replied to?

The communications delay between Earth and Mars is approximately 20 minutes. We're either viewing the light from Mars in the future, Einstein's past dimensions of space-time or in real time, which do you think is more logical? The speed of light according to Einstein's relativity is 186,000 miles per second, but according to physics if two mechanical watches were synchronized on earth and one traveled across the universe and back, there would be no difference in time between the mechanical watches proving the speed of light is instantaneous as the only way a mechanical watch will run slow is if you tighten the main spring :-). Big Bang, Einstein's relativity-time dilation and nearly all of science debunked. There are 7.7 billion people on planet Earth, yet I was the only one who knew I was viewing the light and images of the universe in real time, maybe I should be working for NASA or Elon Musk :-) Light waves can stretch, bend-curve and occupy a state of superposition, whereas the hypothetical Einstein projectile light particle (photon), a particle that has never been observed cannot be both a particle and wave. There are no space-time fantasy unions or gravity waves that can join a particle, wave and time together then bend, curve and stretch them like a rubber band. Neither time nor mass can create itself into nothing, reside in nothing or expand into nothing simply because nothing has no properties. Time and space are independent of each other, not material bodies or fantasy unions that magically stretch time like a rubber band into space-time dimensions. The James Webb Space Telescope is not a time machine, you can’t travel back in time to view the beginning of the universe with telescopes that were made in the future :-). Light and electromagnetic waves are independent of each other. If science uses Einstein's speed of light like an odometer to calculate past dimensions of distance and time, then using the same odometer to calculate forward dimensions of distance and time would mean the Big Bang was created in the future before time existed. The speed of light can be slowed from 186,000 miles per second down to 38 mph by shooting a laser through extremely cold sodium atoms acting as “optical molasses” If the universe were suddenly destroyed, collapsed or fell into a black hole do you honestly think slowing down the speed of light with sodium atoms would save the earth from being destroyed, giving people on earth time to find another planet to colonize and destroy :-). Using optical clocks, lasers and GPS to prove Einstein's time dilation-space-time curvature is like using a metal detector to find gold at Fort Knox. The closer you are to the electromagnetic fields, mass and gravity of the earth the more light bends aka gravitational lensing. Unlike the electron beam of a CRT-TV or high definition LED-LCD television the images we are viewing in the universe are in real time, not a series of frames that create the appearance of a moving image. There are no DCU digital convergence circuits in space :-). If black holes reside in a region of Einstein's theorized space-time where gravity and mass are so dense that nothing, neither mass-particles nor electromagnetic radiation such as light can escape then how could it be possible for the entire mass of our universe to escape the unimaginable density of the proposed Big Bang? According to general relativity sufficient compact mass-density will deform space-time to form a black hole which obviously debunks both Big Bang theory and relativity! Big Bang theorists rely on red shift to support the hypothesis that the universe is expanding, the very phenomena that supports the hypothesis of a (non-expanding static universe). You can duplicate the ion thruster jets of a black hole in a vacuum using a Tesla coil or build one using high voltage-an array of magnets-a CRT-TV yoke or inductor coil. Black holes are nothing but plasma driven vortex electromagnetic fields expanding electromagnetic waves in space. Since the vortex of black holes are thought to be at the center of all galaxies they might be the very force that created them. Gravitational lensing occurs in all wavelengths of light including (red shift-microwave background radiation). Gravity from huge celestial objects of galaxies bend, curve and expand light giving the appearance of what Einstein wrongly theorized as time dilation-space-time-debunking the big bang. Mass from galaxies, planets and black hole electromagnetic fields bend, curve and expand light giving the appearance of what Einstein wrongly theorized as time dilation-space-time dimensions. Light like all electromagnetic radiation and electricity is the result of moving electrons, as moving electrons of charged electromagnetic waves-light travel through the plasma of the universe each lump (or "quanta") of energy in the electromagnetic waves are charged then discharged to the next lump, eventually the energy dissipates causing the delay in radio communications giving the appearance of time dilation - the appearance of longer wavelengths in red shift. Light and electromagnetic waves are independent of each other. If space was curved-warped according to Albert Einstein's curved-warped gravity theory, like a boat in the ocean these same gravity waves would affect time and the perfect balance in solar system orbital mechanics throwing planets off course-out of orbit in a collision course towards the sun where a planets gravity and time would increase and decrease with different velocity rates as they ascend and descend the curves of gravity waves. Using optical clocks and lasers to prove Einstein's time dilation-space-time curvature is like using a metal detector to find gold at Fort Knox. The closer you are to the electromagnetic fields, mass and gravity of the earth the more light bends aka gravitational lensing. If gravity is the result of mass then before the universe came into being gravity couldn't have existed simply because mass was not yet created! Galaxies with massive gravity from the early Big Bang would have been gravitationally bound like the Andromeda galaxy is to the Milky Way galaxy, the sun, moon and planets in all solar systems in the universe yet these early galaxies were able to somehow escape these massive gravitational forces continuing to expand at an increasingly faster rate. Into what, nothing? Nothing has no properties! Neither the atom, universe nor time can be created or destroyed. Albert Einstein an autistic violinist patent clerk that had access to more papers than Suzanne Somers litter box yet creates theories with more bugs than Terminix. If the light from the universe travels from past dimensions of time then it's light is traveling into future dimensions of time (instantaneously). “And God said, Let there be light: and there was light.” a state of superposition where time, and gravity run inwardly, outwardly, in all directions in the same time frame, similar to the electromagnetic field having no beginning and no end. If space was curved-warped according to Albert Einstein's curved-warped gravity theory, like a boat in the ocean these same gravity waves would effect time and the perfect balance in solar system orbital mechanics throwing planets off course-out of orbit in a collision course towards the sun where a planets gravity and time would increase and decrease with different velocity rates as they ascend and descend the curves of gravity waves. Using optical clocks and lasers to prove Einstein's time dilation-space-time curvature is like using a metal detector to find gold at Fort Knox. The closer you are to the electromagnetic fields, mass and gravity of the earth the more light bends aka gravitational lensing. Neither time nor mass can create itself into nothing, reside in nothing or expand into nothing simply because nothing has no properties. Time and space are independent of each other, not material bodies or fantasy unions that magically stretch time like a rubber band into space-time dimensions. Einstein's disciples believe the light and moving images they see in the universe aren't really there, they're just recorded images of the past 13.8 billion years ago. You could lead a cult to water, but you can't make them think. Albert Einstein, an autistic violinist patent clerk that had access to more papers than Suzanne Somers litter box yet creates theories with more bugs than Terminix-Magnetron.

@@michaelbariso3192 none of that's true and most of what you just said makes no sense.

@@Nuclearburrit0 I remember a similar event in "The Life of Brian." In response to the teacher saying "you are all different," one person said "I'm not."

Disregarding whether that insider is real and speaks truth: astrophysics is a masonic LIE.

Yes! well, erm.. no! well.. um maybe? Definitely maybe! What perspective are you thinking things deform from? The perspective of the object? the perspective from that of the transmitter? or the perspective of that from the receiver? If you are of the perspective of the object/particle/wave/energy that is moving through space: then as @Strenkor En'Triel said: no. the object/wave does not get bigger nor longer than what it was when it was sent on its journey. If the perspective youre asking from is either side of receiving it or transmitting it, then yes it APPEARS as such that the universe is expanding it. a good example of this is as @Sander Bouma stated: CMB at least, thats the way ive heard why the cosmological constant matters in regards to the CMB. tl:dr no objects are stretched: but stuff moves away such that things look longer. its all about perspective. Edit: so as @Strenkor En'Triel Strenkor En'Triel suggested, my explanation was a little lackluster so i hope ive corrected the points.

Yep. That's what causes cosmological redshift.

more like, gravitational waves pushing everything apart. Much interfering waves inside galaxies and superclusters and whatnot preventing them from expanding apart. But everything else yes. No need for dark energy with this.

Yes and CMB is a great example of that

Why does google say light travels faster than space expands.

42

Maybe the big bang started in a black spot before the previous universe ended

@@osmosisjones4912 Spam more, maybe you'll learn something if you could be slightly more annoying.

Yes, the speed of light. But the speed of light is relative, so also no.

@@BongoBaggins Most galaxies are moving away from us faster than c

Science doesn't say it doesn't exist below that. It just states our physics break down at that scale.

Probably not cubes.

According to QM , is not a limitation of our understanding per se. Our currently understanding states it is just not posible. What can be wrong is our understanding.

@@aw7049 So QM says it is the absolute minimum?

My understanding is that the amount of energy needed to probe smaller and smaller becomes larger and larger. Plank introduced h to solve the black body radiation problem. But where it really comes to live is in the uncertainty principle. No measurement can be done more precise than h/2 because it would make the “paired” property too big.

we do know that time travels faster and slower in various places. The only constant is the speed of light. So you are technically right, each point of spacetime is older or younger in reference to any other point. Note: As I understand it, anyway (as a layman). If I'm wrong and someone with more physics expertise can explain it better, let me know

We know things in the presence of gravity have a slower passage of time. This is a good question!

It feels like void should have a slower passage of time but it's the opposite apparently and it's annoying

I'm only a dilettante but that sounds inconsistent with the idea of galaxies moving away from each other

@@williamrosenbloom215 No, if everything shrinks in a fixed space, and the measuring units with it, it just seems like it's moving away. Or let's say, the distance gets bigger, but only relative to the measuring unit. @imu The point of view of shrinking objects feels also much more natural to me. In that case you also don't have to "create space", whatever that should mean...

I thought the same thing... the observable universe is expanding away from us until it crosses a horizon we will never be able to see beyond... when you start talking event horizons it is a discussion of 'light cones' and 'observers'... our only observation is from Earth, what would an observe that is already outside of our 'universal event horizon' experiencing? Everything flying (contracting) towards them from our direction!... I agree completely, Observer Bias to a degree!

They would see the same thing but from their perspective, if the universe started off as a singularity that would mean that everywhere is the center

i bothers me. one day we will find out everything is wrong and based off one random guys thoughts 100 years ago

Well, we do have a roughly homogeneous observable universe, based on observation.

@@adlockhungry304 No, observations are about isotropy, not homogeneity.

@@Faustobellissimo nope. but if it bothers you, think about the negation of that assumption. if you are smart enough, that should bother you even _more_

@@DrWhom WHY?

Interesting. Actually, the light changes its speed while traveling through different substances. What if the intergalactic space has more density? The speed of light there would be slower, and we have the sense that the distances are bigger.

Tired light models were basically debunked: en.wikipedia.org/wiki/Tired_light

@@yury7595 that's a different thing - the photons travel just as fast (c, always c) between different scattering events, but there are more of the latter in an optically dense material. Think relay race or pinball machine.

If light were slowing down across the universe it would be affecting things via good old E = mc^2, which would cause problems. If somehow it moved slower in intergalactic space we'd need an explanation WHY. Light generally moves faster in less dense media, not slower, and the rate seems to have been changing over time which would require a change in space itself or whatever filled it.

@@woodypigeon will do! Thanks.

I believe "gravitational bound" refers to any chunk of matter that will not be separated despite dark energy on large scales. This would refer to local groups of galaxies which end up collapskng into a supergalaxies and get separated from all the other supergalaxies due to dark energy on large time scales

Expands yes.... and does it recontract or?

Agreed - furthermore I wonder if in this sort of "boundary layer" between gravity and expansion there is some sort of "Lagrange Point" where an object is in equilibrium between the gravity well and the universe expansion

Glad I stumbled onto this comment!

he can do a video, explaining why it is a non-starter, and then you'd be less happy than you are right now

Repent to Jesus Christ “For there is one God and one mediator between God and mankind, the man Christ Jesus,” ‭‭1 Timothy‬ ‭2:5‬ ‭NIV‬‬

@@seekhimwithallyourheartand3358 -- This sort of behavior doesn't help your cause; it only makes you and your cause look fanatical.

@@seekhimwithallyourheartand3358 like the other guy said, this just makes you sound like a lunatic

You have, it seems, exposed a weakness in this entire argument: for the whole Universe is, in one sense, a "gravitationally bound" system -- every part of it experiences the gravitational attraction of all the rest -- UNLESS there is the still undiscovered graviton, which, as a quantum particle, would presumably have (as with distance and time) a planck-related minimum: below this level the force does not exist, or at least "is not defined."

As I understand it, the Milky Way and the Andromeda galaxies don't have any velocity relative to each other except for that caused by the contraction of spacetime. To put it another way, there aren't rocket engines on each galaxy applying force to them so that they move towards one another. Instead, the distance between the galaxies is decreasing because the spacetime between them is contracting due to gravity. Gravity doesn't act on objects; it acts on spacetime, and the objects just come along for the ride. Gravity acts over unlimited distances, but it decreases with distance. After a certain distance, the amount that gravity contracts the spacetime between two objects will presumably be less than the amount by which empty space wants to expand. There probably is a way of calculating when that will happen, but I don't know what it is.

Stretching space time means affecting the velocity of light. I have another idea, what if the universal constants are changing over time (say velocity of light is decreasing) so that the expansion of space is an effect of that?

So just like One can't tell the difference between Einstein's thought lab moving by rockets or a nearby gravity source, what if all mass is slowing somehow?

@@BiswarupRay in another video he talks about time being a side effect of gravity due the the constant inward acceleration of space due to gravity. if youre far enough in space away from anything, no actions will ever interact with you so basically no time will happen. what im proposing is that all gravity sources are stretching out the light making it only look like the universe is expanding just like a box accelerating up and a room in earths gravity can be indistinguishable.

@@wingnut2292 thats what im getting at! idk about slowing but wouldnt all light leaving earths gravity well be stretched by the gravity just like it can be bent by gravity? thus making it look like everythings expanding

Conservation only applies locally

pretty sure whatever law we invented to explain what we currently see would not apply anymore if we had a bigger picture

There are two ways to look at this. The first is that energy conservation, like all conservation laws, requires a symmetry. In this case, that space not expand or contract. If it DOES, then energy conservation as we know it breaks down. (So, for example the CMB goes from high to low energy photons.) Alternatively proponents of the 'zero energy universe' state that a higher conservation law applies. In the same way that conservation of mass is not a true law (Being broken by the interconversion of mass and energy) energy conservation is an approximation of a true conserved quantity, the energy momentum 4-vector.

spacetime is not expanding, space does

Says you.

👍🏼

Nobody knows because as a species we are absolutely clueless due to not even being capable of exiting our own planets orbit and returning safely.

it's not. The whole theory is bonkers and not even properly falsifiable. They base the entire theory on a single observation: red shift of light from distant objects. This observed phenomenon has potentially other explanations, perhaps some of which we haven't thought of yet. The whole theory is nuts. Yet this is the state of modern cosmology. It's crazy with a foundation of more crazy.

The laws of physics that apply within the universe don't necessarily apply to the universe itself. The new zero-point energy doesn't have to "come from" anywhere, just like the Big Bang didn't have to "come from" anywhere.

@@deusexaethera billions of new plank lengths take energy to maintain a constant energy level no? Where does it get the energy from if not within our universe (all we know that exists for sure).

Eventually all matter will fall into black holes as gravity and frame dragging slow everything down. Humans won't be around to see this though. Likely we will destroy ourselves long before that :(

@@captainzappbrannagan All matter will not "fall" into black holes, but "pushed" into black holes.

@@joseluisalcantarasanchez269 It will be pulled by gravity into the black hole, fall is appropriate. Where is the push coming from?

@@captainzappbrannagan Space wants to be empty so it pushes matter together. Gravity is not attractive, it is the tension of space in the presence of matter and since all matter is moving, it all ends up conglomerating. Think of this: a particle in space, is it occupying a portion of space, or is it displacing space and replacing it with itself?

Interesting. Or how about just cosmic dust and debris? The further light has to travel to reach us the more material it will have to pass through. Material slows light, lightspeed is only constant in a vacuum, this would create a red shift like effect. Also do all spectrums of light move equally between material? Could we be witnessing a filtering effect? Or most interestingly we could actually be at the center of the universe and all the light sources are doing exactly what they appear to be doing - flying outward away from us.

probably not since youre talking about quanta

@@hyperduality2838 your words are useless

I think 09:00 sums it up, we don't have a theory for what space is actually made of.

thanks for the idea

Would we detect a boundary region where the forces are equalized? That would be interesting almost a literal bubble.

Space doesn't actually exist as the entire spacetime is and always has been an infinitely dense point when compared to a bigger reality. Its just that objects made of quarks and atoms expand with in relation to their surrounding and this makes the distance between any two objects made of matter and energy increase.

That would be conceptually elegant - the "new space" created by the expansion is "dark matter", whatever that might be. But that's probably too elegant to be true :D And besides, we have no idea how to test that...

Yep, pretty much. They represent patches in the early universe where gravity was overcome by the effect of dark energy due to a lower density of matter present in these regions and it created these spots where space can expand freely which compounded over several billion years resulted in these humongous voids.

@@ThatCrazyKid0007 Wow...that's amazing. Honestly, didn't think much about it until this video. Thanks for your answer.

Stretching away infinitely...

Yes and no. Time appears to be relatively static in it's scale outside of dilation as a result of extreme velocity, and resultant relativistic mass. If we assume that each object (read particle) in the universe is itself at rest (from it's own perspective, aside from any greater external masses exerting force), which they are, then the difference in the rate at which time 'moves' does not change, only apparent distance.

There are fairly sudden changes between space filled with mass (like the literal insides of stars) and near vacuum. In space of similar density, the change is pretty smooth, yes. I think it might be important to remember that a time-like geodesic is any path that an object of negligible mass (for the scale under consideration) could move along if only affected by gravity and momentum, i.e., an orbit, or a ballistic trajectory, or a fall (all arguably synonymous terms).

A question I've been asking for a while as well but have never gotten an answer to.

As far as I know actually it is speeding up, but ... Look up: "How Is The Universe Accelerating If The Expansion Rate Is Dropping?"

I don't think there is a logical reason to believe they have slowed down since they emitted the light we recieve today. The farthest galaxies discovered are almost as old as the universe itself and if they behaved significantly differently than our closest neighbours, there would already be big headlines about it. Unless you're talking about galaxies slowing their recession over time being the reason we percieve the closer ones traveling slower. In that case, you can prove that galaxies are accelerating regardless of their distance from us based on at least 3 measurement at different times. That must have already been done.

@@filipsperl I don’t quite get how this 3 measurements would prove that the expansion is accelerating

Measuring the same galaxies over time?

As I understand it, it's just that a "point" in the geodesic sense does not refer to "a vertex in the planck length grid". The former is infinitely densely packed (you just pick your "point"), while the latter is finite per volume of space. The grid stays constant, but the coordinate system in which the grid is defined is infinitely finely scalable , and a "point" is an arbitrary coordinate. Remember that the planck length is a distance and not an absolute position.

I think because the plank length is just a relative distance for us to measure not an actual "thing" that would get bigger or not, I think if a random quark (I'm no scientist) was hanging out alone in empty space the expansion wouldn't get so big around it that it suddenly loses meaning in how we understand physics which is what the length is for if that makes sense (?)

Yes

Yesn't

Hmm interesting thought

Why distance between sun and earth is not increasing

Repent to Jesus Christ “For there is one God and one mediator between God and mankind, the man Christ Jesus,” ‭‭1 Timothy‬ ‭2:5‬ ‭NIV‬‬ J

Yes. Just one problem, can you show any way for light to go twice as fast? Because everything we know so far says that is impossible and there has never been any observation showing such a thing.

Good question - I recall from college physics class that Maxwell's equations can be used to solve for the exact speed of light based on some other constants. I suppose those constants could be slowly changing. I think the red-shifting of light emitted by galaxies billions of light years away is evidence space is expanding rather than light slowing down.

@@RobertWF42 isn't the red shifting observer dependent. It has to do with the location of the observer.

No that wouldn't work as so much of fundamental physics is dependent on the speed of light, for example the fine-structure constant would then be time dependent and this would show up in spectra of the early universe. That said, however, you could have a shrinking matter universe under rescaling of dimensionless constants which in every way reproduces the observed expansion. There is no way to tell the difference between shrinking matter and expanding cosmologies.

@@wingracer1614 Yeah, but light going twice as fast would still be OK, since it wouldn't be "faster than light" The speed limit is not 3*10^9m/s, it's the speed of light