Indeed.We are like small fishes in a fish bowl, trying to figure out whats outside but it is out of our bounds at current technological level.So it would take us long time to unravel that part.

The 4% only came in when the accelerated expansion of our universe was discovered, soon coined “Dark Energy” (aka cosmological constant and still confused with the vacuum energy or vacuum expectation value, which is a different story). It was this discovery that affected my assessment of how much we do NOT know – yet.

I’m honestly surprised that the part of the universe makes up even 4% of the Universe. There is so much space between even planets even galaxies. I would like to see some evidence for this by looking at planetary bodies within our solar system. There must be so much evidence for this theory that people would feel confident to assert that. I would enjoy learning this for myself.

I think that is awesome that we know only the 4% of the Universe.

I think we have made great strives in discovering what the universe is and how it works. How awesome is it that from our little planet earth, a speck in the cosmos, and our tiny heads we were able to discover the universe in which we blindly swim, tap on hidden physics laws, and extrapolate to the big bang origin and the perceived indefinite expansion!

As befits our species, we follow simple Darwinian principles – grope blindly forward into uncertainty, sit awhile to admire our achievement – then back to crawling on!

Hello Ladies and Gentlemen,

Thanks to Prof. Mike Turner for this incredible course and it`s clarity.

4%, 26%, 70%- these are the figures for visible matter, dark matter and dark energy.

Prof. Turner has stated we may be a long way from understanding dark energy, the term which he has named.

Prof. Turner cites it may be the 22nd century before dark energy is fathomed.

He has said this for many reasons.

So we see our sciences linked to tool extension- using our senses we have explored the 4%.

Exploring the 26% & 70% of dark matter and dark energy may not be possible without new tools.

Prof. Barry Barish has a really good talk about funding projects at the near end of his course- and funding of projects may take centuries. Then wars happen and drain everyone, first by conflict, then equally by aftermath.

The aftermath of projects waiting for funding can be immense, often awaiting a new generation to clear the backlog.

It really does take that long.

So if our 4% of non-assisted science has occured, the remaining 96% may only occur when new tools for non-human senses develop.

Optical ranges are often said to be limits. The other spectrum of the electromagnetism of gamma, x-ray, ultraviolet are where tools can extend perceptions.

Optical, infrared, and radio waves perhaps are more easy to develop devices for.

May be there is conversion of mass into dark matter to energy to dark energy! An equilibria

Our drop has grown in the ocean of knowledge that surrounds us someday we might get to a half full glass! Exciting times with JWST and LIGO, and all the rest, new knowledge flowing into us from so many directions, I can’t wait to see what comes to us in the future.

Not at all! The cosmos is a huge place and there’s much to be learned. We’ve come a long way; we have a long way to go.

Look at it this way:

If research had been done as much on the 96% as on the 4%, that would have taken away from the 4%. Scientists are studying what’s out there. There are just so many of them and just so much time they and their graduate students and their post-docs each has. The pie has to be divided. If they have X amount of time to spend, it’s going to be divvied up and we’re going to have the same, total amount of research done no matter on what it’s done.