James' World 2

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JANNA LEVIN: It’s such a pleasure to be here tonight.

I wonder how many of you have reflected on this phenomenon: everything anyone has ever seen, or ever will see, makes up less than 5% of what is out there in the universe.

All the people, all the faces, all the mountains, the moon, the stars, the galaxies, supernova—everything we’ve ever seen—is less than 5%. The rest is in the form of dark matter and dark energy, as yet unknown.

And the “dark” phrasing is a misnomer. The dark energy is in this room right now. It fills the room. The dark matter is coursing through you right now. They’re not dark; they’re invisible.

I wonder—and maybe you’ve wondered yourself—what is all this dark stuff? Where does it come from? What is it? Or maybe you study astrophysics, and you actually build detectors deep in mines, waiting patiently for years for one dark matter particle to strike your detector. Yet, despite its abundance, the dark matter has never revealed itself.

It could be that it never will, that we’ll never identify exactly what it is. But maybe you’ve reflected on this strange disparity between us and this dark universe. Or maybe this is your first time hearing all of this.

Imagine us as a collection of confetti tossed amongst this impassive void—sparkling because we are luminous—and yet, to the dark matter, we are as invisible to the dark sector as the dark sector is to us.

Consider the visible universe: you can see your hand because the atoms in your body scatter light, your eyes absorb that light, and that light triggers an electrical impulse along nerve endings. That ignites in your mind an image, the qualia of the visual world. You can feel your fingertips because atoms interact. You can smell and taste because of chemical interactions. Your heartbeat is regulated by electrical impulses from specialized cells.

This is the world we know: the visual world. It’s electrical, it’s magnetic, it’s the world of atoms and of light.

But it’s not just our microcosm. This is the same material that burns in stars, the same light that shines from stars, the same matter lingering from the Big Bang. This is everything everyone has ever seen and ever will see.

If we spiral out to the large scale, we enter the domain of dark matter and dark energy.

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Everything ever seen — every star, mountain, and face — makes up less than 5 percent of the universe. Astrophysicist Janna Levin reminds us that the rest — dark matter and dark energy — is invisible, mysterious, and everywhere. We are the luminous exception in a universe of darkness.

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Click the link below for the complete article (sound on to listen – 13 minutes) (click transcript to read article):

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