Astronomy Picture of the Day 9-17-02

NASA ^ | 9-17-02 | Robert Nemiroff and Jerry Bonnell

[petuniasevan]

Astronomy Fun Fact:

If you remove all the energy from a space, take out all the matter, all the heat, all the light... everything --
you will find that there is still some energy left.

The Heisenberg Uncertainty Principle* states that it is impossible to have an absolutely zero energy condition.

* "The more precisely the POSITION is determined, the less precisely the MOMENTUM is known"

The universe is like a vast ocean, and all we see is the surface.

[petuniasevan]

[Freedom2specul8]

I remember something about "The Heisenberg Uncertainty Principle" in astronomy...but the example above, (the millimeter ball) has me completely lost.

"toward a smooth plate in response to energy fluctuations in the vacuum of empty space. "

....what is the vacuum" and how was it created in the experiment? Sorry in advance if this is a completely naive elementary question..

[petuniasevan]

I admit I'm getting close to the edge of my knowledge here. IIRC, quantum theory says the vacuum and its energy fluctuations underlie all matter and energy. That means the experiment doesn't need to CREATE a vacuum; its effects are always present.

Physicist, am I on the right track here or just spinning my wheels?

[MeekOneGOP]

Cosmic bump !!

[2Trievers]

Heisenberg Uncertainty Principle

An odd aspect of Quantum Mechanics is contained in the Heisenberg Uncertainty Principle (HUP). The HUP can be stated in different ways, let me first talk in terms of momentum and position.

If there is a particle, such as an electron, moving through space, I can characterize its motion by telling you where it is (its position) and what its velocity is (more precisely, its momentum). Now, let me say something strange about what happens when I try to measure its position and momentum.

• Classically, i.e., in our macroscopic world, I can measure these two quantities to infinite precision (more or less). There is really no question where something is and what its momentum is.

• In the Quantum Mechanical world, the idea that we can measure things exactly breaks down. Let me state this notion more precisely. Suppose a particle has momemtum p and a position x. In a Quantum Mechanical world, I would not be able to measure p and x precisely. There is an uncertainty associated with each measurement, e.g., there is some dp and dx, which I can never get rid of even in a perfect experiment!!!. This is due to the fact that whenever I make a measurement, I must disturb the system. (In order for me to know something is there, I must bump into it.) The size of the uncertainties are not independent, they are related by
  • dp x dx > h / (2 x pi) = Planck's constant / ( 2 x pi )

  The preceding is a statement of The Heisenberg Uncertainty Principle. So, for example, if I measure x exactly, the uncertainty in p, dp, must be infinite in order to keep the product constant.

  This uncertainty leads to many strange things. For example, in a Quantum Mechanical world, I cannot predict where a particle will be with 100 % certainty. I can only speak in terms of probabilities. For example, I can say that an atom will be at some location with a 99 % probability, but there will be a 1 % probability it will be somewhere else (in fact, there will be a small but finite probabilty that it will be found across the Universe). This is strange.

  We do not know if this indeterminism is actually the way the Universe works because the theory of Quantum Mechanics is probably incomplete. That is, we do not know if the Universe actually behaves in a probabilistic manner (there are many possible paths a particle can follow and the observed path is chosen probabilistically) or if the Universe is deterministic in the sense that I can predict the path a particle will follow with 100 % certainty.

  A consequence of the Qunatum Mechanical nature of the world, is that particles can appear in places where they have no right to be (from an ordinary, common sense [classical] point of view)!

  This notion has interesting consequences for nuclear fusion in stars.

[sleavelessinseattle]

I need to apply vacuum energy to my couch...Too much popcorn has stochastically deposited itself in a thin film emulsion on its energy boundary...

[2Trievers]

[sleavelessinseattle]

I like the phenomenon that has been detected around Black holes as the example that makes the most concrete sense...
The reason vacuum energy is so hard to detect is that two events happen simultaneously...an electron and its opposite or antimatter particle a positron...appear spontaneously in a sort of circular path going in opposite directions and their trajectories always curve back in and they collide annihilating each other so precisely that no remnant of their existance remains in our universe...This Quantum event happens everywhere, it just is impossible to be there exactly when it happens with any certainty...At the event horizon of a black hole...the gravitational pull is so strong that these little trajectories don't complete their manifest destiny and annihilate each other...little orphaned particles and antiparticles MISS their anti's and survive...and this causes radiation that is detectable...Hawking surmised that this effect exists and there has been some observational evidence that indeed Black holes DO produce the predicted amount of radiation to indicate this unique behavior...

[sleavelessinseattle]

SPIT TAKE!!!

[null and void]

Kewl a MEMS picture. That's the sort of things I make for living. (Anyone hiring out there????)

[BossyRoofer]

Awsome! Good job APOD!

[Freedom2specul8]

LOL!!! I love it..

[Freedom2specul8]

Tis a wonderful lesson..thank you. I found this
Measurement in Quantum Theory
The problem of measurement in quantum mechanics arises out of the fact that several principles of the theory appear to be in conflict. In particular, the dynamic principles of quantum mechanics seem to be in conflict with the postulate of collapse. David Albert puts the problem nicely when he says:

The dynamics and the postulate of collapse are flatly in contradiction with one another ... the postulate of collapse seems to be right about what happens when we make measurements, and the dynamics seems to be bizarrely wrong about what happens when we make measurements, and yet the dynamics seems to be right about what happens whenever we aren't making measurements. (Albert 1992, 79)

I got lost trying to figure out postulate of collapse

But oh to read refreshers :) My brain needed this.... exercise sort of thing.

Thanks guys!

[Freedom2specul8]

That is amazing and easy to understand..thank you. I just heard fox news discussing a newly discovered medium size black hole found in a cluster of stars. So since you brought that, up, I had to look for an article about it. :)

Hubble Spies 'Missing-Link' Mid-Size Black Holes

Tue Sep 17, 3:46 PM ET

By Deborah Zabarenko

WASHINGTON (Reuters) - Astronomers have detected what could be a "missing link" in the development of the universe: mid-size black holes that are neither supermassive nor as small as a single exploded star.

Reuters Photo

The middling black holes were spotted using the Hubble Space Telescope ( news - web sites) in two separate globular star clusters in Earth's celestial neighborhood, astronomers said on Tuesday at a briefing at NASA ( news - web sites) headquarters.

"These intermediate black holes were the missing link," said Steinn Sigurdsson of Pennsylvania State University.

While astronomers have known for years about vastly large black holes and rather small ones, Sigurdsson said, "We didn't know if we could get from one to the other or if they were completely unrelated, and this seems to be the step that takes us from one to the other."

Black holes are unimaginably dense regions in space whose gravitational pull allows nothing, not even light, to escape. For that reason, black holes are invisible but can be detected by the pattern of swirling stars and gas around their edges.

In the past several decades, black holes have gone from being rare and almost mythic phenomena whose existence was routinely questioned to being accepted by most astronomers as a feature of the cosmos.

Until now, though, black holes were thought to come in two basic sizes.

There were so-called stellar-mass black holes, created when stars about 10 times the size of our sun died in big explosions called supernovae.

Then there were supermassive black holes believed to lurk at the center of galaxies, including the Milky Way that contains Earth. Those black holes could have the mass of millions or even billions of suns.

BLACK HOLES WITHIN SWARMS OF STARS

Astronomers wondered whether there was a mid-sized version, and now they have found two of them, not in galaxies or floating free, but in tightly packed swarms of stars called globular star clusters.

Both fit the profile of what a mid-size black hole should be. The first, in cluster M15, has about 4,000 times the mass of our sun; the second, in cluster G1, has about 20,000 solar masses.

Because globular star clusters contain the oldest stars in the universe -- the smaller of the two mid-size black holes is in a cluster 13 billion years old -- information about them could help scientists figure out how the clusters form.

Mid-size black holes are in a "very important mass range," according to Karl Gebhardt of the University of Texas at Austin.

"That has implications for how you make a supermassive black hole and it is possible that these black holes can act as the seeds on which you make the supermassive black hole," Gebhardt said.

Scientists found a powerful pattern in the mid-size black holes, Gebhardt said. Their mass was related to the mass of the star cluster in just the same way the mass of supermassive black holes is related to the mass of the galaxies that contain them, he said.

"That has implications for how a globular cluster is related to a galaxy and how a galaxy is formed," he said.

Images and more information on the findings are online at http://oposite.stsci.edu/pubinfo/pr/2002/18.

[2Trievers]

Use it ... or lose it! Get those snapses going! &;-)

[Freedom2specul8]

Am trying !! :) I've grown a few connections in the past few months, but they were connected to the wrong places.. When I drive a car, I think chocolate. When I read a book, I think chocolate. It's just ~wierd~ ;-)

http://www.netacc.net/~gradda/sp94brai.html
"Try as I may, I cannot, TO SAVE MY LIFE, understand about the DOPAMINE uptaking thing a ma jigs, the snapses (on shirts?) nor the neurotransdingers. Do you have diagrams, charts, or FILM AT 11 about all this in your book? If not you could begin a collaborative effort with DISNEY on educating us ADDers about why our BRAINS are wired differently! "

[2Trievers]

My solution is to find yourself a BF who leaves Belgian chocolates by your bed when he is away ... drives a REALLY awesome car ... and writes his own books of poetry to you. Then those synapses will just seem to be a distant memory, hardly worth the worry. The only ADD that will concern you is in the COLOSSAL balance in the checkbook. &;-)

[sleavelessinseattle]

That was fun to read! You are a bit advanced for it but I still enjoy some of the concepts from Gary Zukov's Dancing Wu Li masters, if you haven't read it, its a bit metaphysical but it helps chase away the cobwebs without causing a Cerebral meltdown! I like the concept of beginner's mind...being open to new paradigms even when you don't necessarily know where they will wind up...To me that is where the quantum aspects get interesting...Its the deterministic emphasis of experimental research that forces the outcome of the measurement into mass OR position...its trying to break the symmetry of the particle down...that is the fundamental error of human thought IMHO...Another fun author, although deceased, and somewhat out of date is Heinz Pagels' Perfect Symmetry.

[Freedom2specul8]

"My solution is to find yourself a BF who leaves Belgian chocolates by your bed ...The only ADD that will concern you is in the COLOSSAL balance in the checkbook. &;-)"
and my concern for my hubby! lol