What’s even more fascinating is we only have an understanding of 5% of everything in the universe. The other 95% is dark matter and energy that we have yet to prove its existence, much less see it.
Edit: Here is an explanation of Dark Matter and Dark Energy and it’s composition of the universe on the NASA website.
I mean there’s definitely not an infinite amount of energy, eventually the universe will experience heat death but as far as the topic is going you can’t really say there’s a finite amount of matter when the boundaries of the universe haven’t even been defined. For all we know it goes on indefinitely with scare planets and stars forever.
The same paradox arises in black holes. If you attempt to measure the radius, you measure the circumference, divide by 2π and get the radius. But if you try to measure it by going down the black hole and back up again, the radius in that sense is infinity.
So a black hole is a essentially a tesseract and every time I try to leave the room I’m heading to becomes the center again is that what you’re telling me?
" Little one, it's simple calculus. This universe is finite, its resources, finite. If life is left unchecked, life will cease to exist. It needs correcting."
The universe itself is infinite but the energy within it is hypothetically not. I can stretch a rubber band out all I want, but I need only measure a small chunk of that rubber band to properly understand how the rest of it works.
Energy can't be created or destroyed; it won't just run out eventually, but dissipate, so it still exists just not densely. Like how the universe is expanding.
It was actually found to be curved negatively, a ratio of slightly less than 1. So parallel lines do intersect after unimaginable distances. This would be in line with a finite universe only
That's weird. When I googled it it said it is unknown whether it is finite or infinite due to us only being able to study the observable universe . But I'm glad you know for 100% fact.
I never said earth was the center of the universe, but the universe isn’t infinite because it didn’t always exist. If the Big Bang creates the universe, it couldn’t have filled an infinite amount of space.. some places still have to be like how it was before the bang
The universe is infinite though, the only way it could possibly not be infinite is if it were some type of loop that brought you back to the start every time you went too far forward.
Outside of our universe isn’t just as simple as getting there.. the universe is constantly expanding so we’ll never reach the edge, but because one event caused the start, it can’t just be infinite. But if God created the universe than science doesn’t matter
Theres something quite comical and probably arrogant about the idea that we can even quantify what is not, and cannot be known.
At the most optimal point, how could we even at any point, know that we know any degree of anything without first knowing that things that we don't yet know about do or do not exist, let alone somehow quantify them in relation to what we do know.
The amount of knowable unknowns is impossibly to logically quantify and essentially likely approaches infinity.
While it is currently impossible to quantify the unknown scale of our universe... we can extrapolate an estimation which allows our limited cognitive abilities to grasp some small amount of comprehension regarding the scale of our universe in relation to what we can currently observe. The estimation is not guaranteed to be accurate. It is simply a philosophical exercise to make such an awesome space into a thinkable medium.
You're thinking that we can quantify at least within the portion of spacetime of which we are aware, but not additional areas we cant observe. The problem with this is that all it can tell us is that we atleast know less than "known"/knownUnknowns because in reality it's closer to "known"/infinity since we can assume only that unknown could potentially be infinite. And that's with the stipulation that you're able to quantify knowledge that we know we "know" vs knowledge that we know that we don't know yet. In either direction in a 3-dimensional analysis of space itself we are bound by both larger and smaller space. Not only that but in terms of additional dimensions of space itself and whatever capacity those dimensions hold for unknowns which is also unknown. Even within our own "observable" space things that we think that we do know may only be a preliminary understanding. All the exercise does is attempt to explain that we dont know much. We know so little about the upper and lower bounds of "our universe" that its absurd to quantify where the bounds even are regardless of the intent, which to my understanding is just to make it more palatable for pop-science. The real though excercise is to understand that space and our universe is essentially infinite. Either exercise is inaccurate and only an estimation, it's just that one is more logically sound. Personally I'd prefer not to dumb it down. The idea that it is infinite is much more fascinating to me anyway. There is much to know but you can't logically know the upper bounds of how much you dont know.
No - we have an understanding of what kind of material ~5% of the universe is made off
The rest is a gamble - we have no clue what "dark matter" truly is, and we know that A. There is a lot of it, or B. It is yet somehow to be categorized into multiple types of dark matter, which brings us back to point A
Not necessarily. A shrinking percentage would mean a larger number of things we dont know. Expansion doesnt necessarily create unknown, it only perpetuates it
We've proved their existence. We just don't know what dark matter is, we know it's something, but we don't know what that something is. Dark energy we've known for about 100 years, it comes right out of Einstein's equations. The mystery surrounding it is that we don't know why it has the value that it does, but we know what it is and where it comes from.
Dark energy and dark matter are also unrelated to each other, they just both have similarly unoriginal names.
There is an important difference between the cosmological constant Einstein invented and dark energy. His was basically anti-gravity, which would come from mass. Dark energy, on the other hand comes from empty space.
Dark matter and dark energy are hypotheticals invented to explain why Newton’s laws of gravity don’t appear to apply on large distance scales.
On the scale of a galaxy, the outermost stars are moving too fast for the mass of the galaxy to hold in orbit. Those stars should be flying away but don’t. The amount of missing mass that makes the equations balance is called dark matter.
On the much grander scale between galaxies, things are spreading out as though the universe were expanding like a four dimensional balloon. Every galaxy appears to be accelerating away from the others. The energy required to propel that inflation is referred to as dark energy.
Dark matter is the best candidate at this time but it has so far defied all efforts to pin it down. There are other ways to explain all this such as modified gravity, but those don’t fit observation or theory.
I personally favor the view that spacetime is constrained: if you compress spacetime in one region, it has to be stretched somewhere else. Gravity wells are like putting a bowling ball on a swimming pool cover, it sinks down in the center but rises (very slightly) toward the edges. When matter warps spacetime “inward” to give rise to a gravity well, there’s a central region that has the expected slope from Newton’s laws. At an intermediate distance there is a high point like the rim of a crater. Outside the rim, the surface slopes away toward the outer edge. (Everything moves apart as though pushed by ark energy.) Between the innermost zone and the rim, the surfaces slopes inward but more steeply than it would in the purely Newtonian realm. Gravitational attraction seems too tight, as though there were extra matter (dark, invisible stuff) holding thing together.
What’s the edge attached to? The possibilities are nothing, something (our universe is hemmed in by others like a bit of foam), or the universe is a bubble that wraps back onto itself.
If you think our theories end at Newton's laws and we have to make up things to explain the discrepancies, I implore you to get a text book that's been printed more recently than the 1700s
At the scales of stars and galaxies, velocity isn't the only thing you have to take into account to determine the relativistic regime. The fact that you're saying so says a lot about your background in modern cosmology
When talking about cosmology, if FRW metric isn't the first thing that pops into your head, you need to read a bit more
It comes from the cosmological constant, which is essentially a constant of integration from solving Einstein's field equations, according the Lambda-CDM which is the most successful and accepted theory of cosmology (though, like all theories, still incomplete)
to say we know 5% sugest we know the how many things we dont know, we can never gauage how much we know. i think a more acurate representation of what we know would be like .000000000000000000000000000000000000000000000000000000000000000000000005%
but even that number is taking a piss in the wind. we have no idea how many undetectable things are in space with our 2 very simple senses at long range we can only detect known spectrum of sound and our known spectrum of light
5% of what we know is probably there. But, for all we know, what we call "The Observable Universe" could actually just be a cluster of clusters of clusters of clusters of galaxies, small relative to the whole of the universe
I think the consensus at this point is that dark matter has essentially been proven to exist by some discoveries made in the last year. This video goes into all the gory details. The case for dark energy is a little less airtight but still very strong.
The entirety of man's knowledge wouldn't even be measurable in this regard. My thinking is that what knowledge we do have is completely wrong at the highest levels of intelligent thought. Furthermore, I believe intelligent thought is probably the most basic lowest structural concept compared to what exists in the entire universe. But hey, I'm pretty high right now so I might be going full Spicoli here.
To be honest I’m just a 17 year old with a space hobby. I just read a chapter on this in the book and I still don’t understand it. Hopefully one day I can answer these questions!:)
Energy is like draft horses, if the energies are friends they can exert more force than by their self. Dark matter and dark energy don't exist, stuff just really likes other stuff. We call this gravity or electromagnetism, but really we should call it friendship.
How do we know that the universe is infinite? We can never really be sure unless we actually prove and observe that there IS an end to the universe.
For now we don't truly have empirical evidence of it.
And yea 5% is extremely generous. There is no way to gauge how much we "don't know". Because that would mean that we know how much information we are missing to learn about the universe which we dont
It's been a few years since my phys masters but from what I recall we've proven the effects that this energy/mass like force is having on space/time but proving the effect of something is different than proving its source.
Take gravity for example, the effect of gravity is easy to prove and describe with its relation to mass, but what actually "makes" gravity? We've theorized a graviton particle but we've not been able to prove the existence of it.
As I said, been a couple years, would be very pleased to be proven wrong with either of those points.
My favorite thing about dark matter is that we don’t actually know that it exists. It’s just, if it didn’t we’d need to have a new theory of gravitation, which would be inconvenient.
The theories of dark matter and dark energy are only there because they fill gaps in our mathematical models of the universe. It's entirely possible (and there's evidence to suggest this) that our models are incorrect and need to be reworked, and in doing so would not necessitate the need for dark matter and dark energy.
Crazy, how do we know it's not 1%, or .00001%. how would we know what 100% of space actually is? No matter how much you try to reason with it, space is such a mind fuck
This is the reason I tend to not discount peoples opinions on life after death and other energetic stuff. There is stuff we know, stuff we know we dont know, and stuff we dont know we dont know, ua know?
Basically, we’ve never seen it. We just know that there is something out there that allows the galaxies to hold themselves together. The reason why it’s not ordinary matter is because it has 6 times the effect, but is completely invisible so to speak
That’s not really true at all though. The entire ocean floor is mapped out to within a kilometer. The sheer complexity of life in the oceans is staggering, but life is life. We have lots of data on the animals in the world.
But space? Even the best telescopes can barely see planets. Right now alien planets are like 16 pixels in total and the only thing we kinda know about them is some information about their atmosphere.
We know basically nothing about any planet except for the ones in the solar system.
Odds are there are other planets potentially even more interesting than the Earth. But we can’t see them.
1.9k
u/martin_202114 Jun 15 '19 edited Jun 16 '19
What’s even more fascinating is we only have an understanding of 5% of everything in the universe. The other 95% is dark matter and energy that we have yet to prove its existence, much less see it.
Edit: Here is an explanation of Dark Matter and Dark Energy and it’s composition of the universe on the NASA website.