(Originally broadcast on June 25, 2008)
NEIL
deGRASSE TYSON: And now for some
final thoughts from the "dark side."
Consider all we've learned about the size, age and contents of the universe, from its fiery birth in the Big Bang, through 14 billion years of cosmic expansion that has followed. Even better, consider the powerful laws of physics we've discovered that account for it all. Kind of makes you stand with pride for being human.
But before you stand too tall, consider that, at this moment, we can account for only about 15 percent of all the gravity we've ever measured in the universe. We're simply clueless about what's causing the rest. Not only that, if you add up all the matter and energy in the universe, it comes to just four percent of all that drives cosmic expansion.
So we're clueless about that one too, with no idea about what occupies the remaining 96 percent.
We call these two entities "dark matter" and "dark energy." What are they? Maybe they're exotic never-before-seen forms of matter and energy, or maybe they reveal a hidden flaw in our understanding of how the universe works. But really, the two terms are placeholders for our abject ignorance. We could just as easily have labeled them "Bert" and "Ernie" or "Without-a-Clue A" and "Without-a-Clue B."
So we are left in a curious situation. What we know of the universe, we know well. Yet a larger cosmic truth lies undiscovered before us, a humbling yet thrilling prospect for the scientist driven not only by the search for answers, but by the love of questions themselves.
And that is the cosmic perspective.
Excellant program highlighting what we don't know to inspire to learn more! Keep up the good work.
Why do researchers believe that Dark Matter should be able to easily penetrate deep into the Earth? Perhaps Dark Matter only exists in space.
Dear Sirs, What if dark matter and dark energy is actually our parrallel universe? Thanks
This was a most interesting comment. Is a transcript available?
Geo,
I just added the transcript to the post.
Rachel VanCott, NOVA Online
Thanks so much, Rachel.
May I have he privilege of forwarding this comment to others in my address book?
And, where can I find a brief biography, say a single page or less, of Dr. Tyson, hopefully with a picture on the same page?
Thanks, again.
Geo
Geo,
You can learn more about Neil at our "About the Host" page.
http://www.pbs.org/wgbh/nova/sciencenow/about/host.html
AN excellent program as Dr. Tyson Brings hi vast knowledge and humor to the program.
Dark Matter Explained:
I do not have any scientific proof for this, but as a thought process, I think that Dark Matter can be explained as follows:
1. Gravity is an electromagnetic wave (Field) of 0 Frequency.
2. The graviton has one end that attracts matter and one end that repels matter.
3. In its normal random state, the gravitons have no net attraction.
4. When the Moon for example aligns the gravitons, they have a net attraction which we can see by the effect on the oceans of the Earth.
5.As other masses pass by the partially aligned gravitons they may add or subtract from the alignment.
6. What is currently considered to be the effect of Dark Matter, is the net effect of the gravitons after being aligned and realigned as visible matter travels throughout space.
? Does gravity travel at a speed?
? How would we measure that speed?
? Can the speed be affected by something locally as in the way that mass can change the speed of light?
Dark Matter occurs when photons (star light) recombine back into atoms. This is the simple formula MC 2 = E (from Einstein).
I'm working on synthetic dark matter in my tiny lab.
Dark Matter is worth about $1 billion per ounce...Alfred Herman Schrader