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Dark Matter Mystery

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Cosmic Perspective from NOVA scienceNOW, August 4, 2009
(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.

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16 Comments

Wasn't there a recent observation of a galaxy which seemed to contain dark matter, i.e the behaviour of the outer regions and the gravtiational pull on nearby objects implied the galaxy had greater mass than could be accounted for.

Dark matter does not exist. It exists because there are some basic problems with our "theory" of gravity. The biggest problem is that there is no mechanism for gravity. Newton does not have a mechanism nor does Einstein. Dark matter is needed because our gravity model is wrong.

Robertson Davies~ The world is full of people whose notion of a satisfactory future is in fact a return to the idealised past.

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Given the exotic nature of dark matter and dark energy, what if the matter exists through time in 3 states similar to that of a neutrino? And the dark energy is the result of a conversion of this dark matter into energy? The three states would be split into influences over time, one constant across time, the others where their influence is reversed but not exactly across time. One of these would have greater influence from its presence in the present and the other would have greater influence from its presence in the past as well as in the future.

Thankfulness so much, Rachel.
May perhaps I give birth to he privilege of forwarding this comment to others all the rage my talk to put your name down for?
And, everywhere can I discovery a mission biography, say a single call otherwise a reduced amount of, of Dr. Tyson, with a bit of luck with a picture on the same call?

Thankfulness, again.
Geo

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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

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? 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 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.

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AN excellent program as Dr. Tyson Brings hi vast knowledge and humor to the program.

Geo,

You can learn more about Neil at our "About the Host" page.
http://www.pbs.org/wgbh/nova/sciencenow/about/host.html

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

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Geo,

I just added the transcript to the post.

Rachel VanCott, NOVA Online

This was a most interesting comment. Is a transcript available?

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Dear Sirs, What if dark matter and dark energy is actually our parrallel universe? Thanks

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Why do researchers believe that Dark Matter should be able to easily penetrate deep into the Earth? Perhaps Dark Matter only exists in space.

Excellant program highlighting what we don't know to inspire to learn more! Keep up the good work.