What is the universe made of?

The Earth, the sun, the stars, and everything we can see, only comprise five percent of the universe. But what about the other 95 percent? Scientists are puzzling over dark matter and dark energy, the mysterious components that make up the rest.

What is the universe made of? Scientists have determined that normal matter, the stuff that makes up the earth, the stars and everything we can see, only makes up a small portion of the universe. The rest is made up of two mysterious components that are shaping our universe in profound ways. Much of the mass of the universe is made up of something called Dark Matter, which neither reflects nor emits light, but like the matter we can see, pulls things together with gravity in. Space itself seems to be permeated by an unusual force called Dark Energy which is driving things apart.

Based on current estimates scientists believe that only 5% of the universe is made up of normal matter, 27% is made up of Dark Matter, and a whopping 68% is made up of Dark Energy. So what are they and how do we know they exist?

Although we can't see Dark Matter we can tell it is out there from the effect it has on regular matter such as galaxies and stars. We can track where Dark Matter is located through an effect called gravitational lensing. According to General Relativity, massive bodies bend the fabric of space-time. That means they bend the paths of light. Astronomers can see this light bending in places where there are no visible chunks of matter, such as stars. It must be caused by Dark Matter. Through these observations, scientists have found a cosmic web of Dark Matter. Vast lumps of long threads of it. It is spread throughout the universe but tends to be concentrated in halos around galaxies. Indeed, it is considered to have been integral to the formation the large-scale structure of the universe.

So what is Dark Matter made of? No-one knows for sure yet but there are a number of theories.

There are a number of different experiments focused on finding Dark Matter, trying to catch it as it occasionally bumps into normal matter, but none of them has been successful so far. Dark Matter particles might just be created in earthly laboratories too. At the Large Hadron Collider in Switzerland, where particles smashed together near the speed of light, there is some chance that Dark Matter particles will pop out and astronomers using some of the world's largest telescopes are observing the cosmos with ever more precision to learn about where Dark Matter is located. It was through their efforts in the late 1990s that scientists learned about the other mysterious force that is shaping our cosmos - Dark Energy.

Astronomers studying distant supernovae discovered it accidentally by observing that the expansion of the universe seemed to be speeding up. Michael Turner coined the term Dark Energy to describe the mysterious force that seemed to be pushing the universe apart.

The idea that the universe could expand or contract showed up in early drafts of Albert Einstein's theory of relativity but Einstein himself believed the universe was of a fixed size. To get things to add up correctly he fudged his equations by inserting a fixed value he called a cosmological constant. Only later when it was shown the universe was in fact expanding that had become apparent that his equations were right to begin with. Einsteins cosmological constant might also end up accounting for Dark Energy. No-one knows what Dark Energy is exactly, although many theories have been postulated.

One suggestion is that it is energy folded into the fabric of space itself. As space expands, so does the amount of Dark Energy, so there will be more of it to push the universe apart. What astronomers don't know yet is if the rate of acceleration of the expansion will change over time. If it does that could have profound implications.

But the dominance of Dark Matter and Dark Energy have shifted over the lifespan of the universe. With Dark Matter playing a stronger role in the early years and Dark Energy gaining traction more recently. What will happen to our universe depends on the interplay between these two dark titans. If Dark Energy becomes more dominant the universe may thin itself out of existence in what's called the big rip. but if Dark Matters influence should increase, that could collapse the universe back upon itself in a Big Crunch. And if neither force changes dramatically space may just continue expanding outward indefinitely.

For cosmologists trying to foresee the ultimate fate of the universe much remains in the dark.

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[theworldeatswithyou]

The background music is too loud compared to the voice of the narrator.

[NightBazaar]

I had to stop the video about halfway through because the background music was drowning out the narrator's voice. At first, I thought my hearing was going haywire. Glad to see I'm not the only one who is irritated by it. Maybe someone should first review some of these videos before uploading them to YouTube.

[leagueoftrolls]

my dream since i was a child was always to be a cosmologist... i remember looking at the stars and how fascinated i was by them and each time i someone told me what would you like to be when you grow up i innocently answered i want to be a scientist that studies the stars only to get giggles as reactions since my answer differed from the other kids who wanted to become doctors lawyers police officers...
the years passed and now im a 22 years old dentistery student looking at this video until my mind noticed the people in it and whispered to my soul "look at how great these people are... take Mr Turner for example look how great he seems and how wise must he be and powerful with the knowledge he carrys... would you able to be like that someday ? would you dare to dream to be like that ? ... " i had tears in my eyes because the actual me hesitated to answer while the child me could have said yes with a big confident smile on his face !...
i now realizr how easy it is to be carried away from your most profound dreams by the whirlpool of society and ending up doing something that you had never in mind or sometimes the exact opposite of what you had imagined for yourself
i hope i can at least live up until meeting these people who for me represent the stars of my childhood sky :)

[ThomasSchranz]

I like that you are creating video content as well. But I think you can increase the quality here. The narrator is too fast and sounds like he's just reading stuff. The background music is too loud in some parts.

hth

[antsmith]

the music is amazing. atmospheric, chilled out, dreamy and ethereal. the narrators voice is brilliant too. it has a nice tonal quality about it. videos like this are very relaxing and great to put on in the background when you lie down.

[tabamal]

The Background Music is loud and confusing..

[watdafak]

Cool vid. Narration a bit low in volume. Keep the music.

[RaysAstrophotography]

Extremely intriguing. Great content and presentation.

[Jackie-wcxk]

Like the video, the music is a little too loud, I couldn't really make out what some of the ppl being interviewed were saying

[illbebackinfive]

The background music is VERY annoying.

[huajieliu]

Wow. This is so fascinating. Dark matter and dark energy are two elements constituting the cosmos. And there are many theories related to these two elements. But we still couldn't tell what they are made of. Further investigation and research are needed.

[brainstormingsharing]

Absolutely well done and definitely keep it up!!! 👍👍👍👍👍

[tpar]

Awesome video, Economist. I'm wowed by the quality of your science videos lately.

[karthikgopal]

Doesnt have to be gravity bending light in space fabric.. could also be normal matter (different layers of density) creating a lens effect.. similar to refraction.. this is a very misunderstood topic - dark energy and dark matter.

[vinhqngouoc]

string theory consist of 10 or more universes assuming one universe cant see the others . so why dont we account the total mass of those universes

[KnIfEzZv]

Fucking love these videos!!! Keep them up!!!!

[stromboli]

I was hoping for a more fundamental discussion of the problem, but some essential basics are ignored. Beginning of the video says "normal matter makes up only a small portion of the universe" and "we know normal matter is made of quarks and fundamental particles".

Ehm... yes, but that hardly explains anything. What IS "normal matter"? What is a quark, or fundamental particle, exactly? What are *they* made of?

Some people say strings, and the frequency at which a string vibrates or resonates, determines as what particle it is manifested. Right.. so what is this string made of? What is it, exactly, that's vibrating?

[teemum.]

Let's figure out how to make energy-matter conversion. We can do matter-energy conversion by nature. That would give us teleporting etc. 3:33 Dark matter is new form of stable matter, which we are yet to identify! Let's consider the multiverses. If our universe is among others popping in and out, what does it mean to the dark matter?

[davidgray]

Frankly I don’t think the vast majority of people can deal with this level of abstract thought. It’s to far from our everyday environment.

[merveyorganci]

I like this video it's amazing. I want to ask about a subject. can you help me? or you can get in direct contact?